{"api_version":"1","generated_at":"2026-11-13T08:31:12+00:00","cve":"CVE-2023-53489","urls":{"html":"https://cve.report/CVE-2023-53489","api":"https://cve.report/api/cve/CVE-2023-53489.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2023-53489","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-53489"},"summary":{"title":"tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.\n\nsyzkaller reported [0] memory leaks of an UDP socket and ZEROCOPY\nskbs.  We can reproduce the problem with these sequences:\n\n  sk = socket(AF_INET, SOCK_DGRAM, 0)\n  sk.setsockopt(SOL_SOCKET, SO_TIMESTAMPING, SOF_TIMESTAMPING_TX_SOFTWARE)\n  sk.setsockopt(SOL_SOCKET, SO_ZEROCOPY, 1)\n  sk.sendto(b'', MSG_ZEROCOPY, ('127.0.0.1', 53))\n  sk.close()\n\nsendmsg() calls msg_zerocopy_alloc(), which allocates a skb, sets\nskb->cb->ubuf.refcnt to 1, and calls sock_hold().  Here, struct\nubuf_info_msgzc indirectly holds a refcnt of the socket.  When the\nskb is sent, __skb_tstamp_tx() clones it and puts the clone into\nthe socket's error queue with the TX timestamp.\n\nWhen the original skb is received locally, skb_copy_ubufs() calls\nskb_unclone(), and pskb_expand_head() increments skb->cb->ubuf.refcnt.\nThis additional count is decremented while freeing the skb, but struct\nubuf_info_msgzc still has a refcnt, so __msg_zerocopy_callback() is\nnot called.\n\nThe last refcnt is not released unless we retrieve the TX timestamped\nskb by recvmsg().  Since we clear the error queue in inet_sock_destruct()\nafter the socket's refcnt reaches 0, there is a circular dependency.\nIf we close() the socket holding such skbs, we never call sock_put()\nand leak the count, sk, and skb.\n\nTCP has the same problem, and commit e0c8bccd40fc (\"net: stream:\npurge sk_error_queue in sk_stream_kill_queues()\") tried to fix it\nby calling skb_queue_purge() during close().  However, there is a\nsmall chance that skb queued in a qdisc or device could be put\ninto the error queue after the skb_queue_purge() call.\n\nIn __skb_tstamp_tx(), the cloned skb should not have a reference\nto the ubuf to remove the circular dependency, but skb_clone() does\nnot call skb_copy_ubufs() for zerocopy skb.  So, we need to call\nskb_orphan_frags_rx() for the cloned skb to call skb_copy_ubufs().\n\n[0]:\nBUG: memory leak\nunreferenced object 0xffff88800c6d2d00 (size 1152):\n  comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 cd af e8 81 00 00 00 00  ................\n    02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00  ...@............\n  backtrace:\n    [<0000000055636812>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:2024\n    [<0000000054d77b7a>] sk_alloc+0x3b/0x800 net/core/sock.c:2083\n    [<0000000066f3c7e0>] inet_create net/ipv4/af_inet.c:319 [inline]\n    [<0000000066f3c7e0>] inet_create+0x31e/0xe40 net/ipv4/af_inet.c:245\n    [<000000009b83af97>] __sock_create+0x2ab/0x550 net/socket.c:1515\n    [<00000000b9b11231>] sock_create net/socket.c:1566 [inline]\n    [<00000000b9b11231>] __sys_socket_create net/socket.c:1603 [inline]\n    [<00000000b9b11231>] __sys_socket_create net/socket.c:1588 [inline]\n    [<00000000b9b11231>] __sys_socket+0x138/0x250 net/socket.c:1636\n    [<000000004fb45142>] __do_sys_socket net/socket.c:1649 [inline]\n    [<000000004fb45142>] __se_sys_socket net/socket.c:1647 [inline]\n    [<000000004fb45142>] __x64_sys_socket+0x73/0xb0 net/socket.c:1647\n    [<0000000066999e0e>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n    [<0000000066999e0e>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80\n    [<0000000017f238c1>] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nBUG: memory leak\nunreferenced object 0xffff888017633a00 (size 240):\n  comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    00 00 00 00 00 00 00 00 00 2d 6d 0c 80 88 ff ff  .........-m.....\n  backtrace:\n    [<000000002b1c4368>] __alloc_skb+0x229/0x320 net/core/skbuff.c:497\n    [<00000000143579a6>] alloc_skb include/linux/skbuff.h:1265 [inline]\n    [<00000000143579a6>] sock_omalloc+0xaa/0x190 net/core/sock.c:2596\n    [<00000000be626478>] msg_zerocopy_alloc net/core/skbuff.c:1294 [inline]\n    [<00000000be626478>]\n---truncated---","state":"PUBLISHED","assigner":"Linux","published_at":"2025-10-01 12:15:51","updated_at":"2026-11-05 21:17:23"},"problem_types":["CWE-401"],"metrics":[{"version":"3.1","source":"nvd@nist.gov","type":"Primary","score":"5.5","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://git.kernel.org/stable/c/cb52e7f24c1d01a536a847dff0d1d95889cc3b5c","name":"https://git.kernel.org/stable/c/cb52e7f24c1d01a536a847dff0d1d95889cc3b5c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/230a5ed7d813fb516de81d23f09d7506753e41e9","name":"https://git.kernel.org/stable/c/230a5ed7d813fb516de81d23f09d7506753e41e9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1f69c086b20e27763af28145981435423f088268","name":"https://git.kernel.org/stable/c/1f69c086b20e27763af28145981435423f088268","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/50749f2dd6854a41830996ad302aef2ffaf011d8","name":"https://git.kernel.org/stable/c/50749f2dd6854a41830996ad302aef2ffaf011d8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/426384dd4980040651536fef5feac4dcc4d7ee4e","name":"https://git.kernel.org/stable/c/426384dd4980040651536fef5feac4dcc4d7ee4e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/43e4197dd5f6b474a8b16f8b6a42cd45cf4f9d1a","name":"https://git.kernel.org/stable/c/43e4197dd5f6b474a8b16f8b6a42cd45cf4f9d1a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/602fa8af44fd55a58f9e94eb673e8adad2c6cc46","name":"https://git.kernel.org/stable/c/602fa8af44fd55a58f9e94eb673e8adad2c6cc46","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/30290f210ba7426ff7592fe2eb4114b1b5bad219","name":"https://git.kernel.org/stable/c/30290f210ba7426ff7592fe2eb4114b1b5bad219","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/281072fb2a7294cde7acbf5375b879f40a8001b7","name":"https://git.kernel.org/stable/c/281072fb2a7294cde7acbf5375b879f40a8001b7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-53489","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53489","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 281072fb2a7294cde7acbf5375b879f40a8001b7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 1f69c086b20e27763af28145981435423f088268 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 602fa8af44fd55a58f9e94eb673e8adad2c6cc46 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 230a5ed7d813fb516de81d23f09d7506753e41e9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 43e4197dd5f6b474a8b16f8b6a42cd45cf4f9d1a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 cb52e7f24c1d01a536a847dff0d1d95889cc3b5c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 30290f210ba7426ff7592fe2eb4114b1b5bad219 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 426384dd4980040651536fef5feac4dcc4d7ee4e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f214f915e7db99091f1312c48b30928c1e0c90b7 50749f2dd6854a41830996ad302aef2ffaf011d8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.14","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.14.315 4.14.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.19.283 4.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.4.243 5.4.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.180 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.111 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.28 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.2.15 6.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.3.2 6.3.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.4 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2023","cve_id":"53489","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2023-53489","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-11-05T20:22:23.206424Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-11-05T20:31:11.838Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/core/skbuff.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"281072fb2a7294cde7acbf5375b879f40a8001b7","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"1f69c086b20e27763af28145981435423f088268","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"602fa8af44fd55a58f9e94eb673e8adad2c6cc46","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"230a5ed7d813fb516de81d23f09d7506753e41e9","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"43e4197dd5f6b474a8b16f8b6a42cd45cf4f9d1a","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"cb52e7f24c1d01a536a847dff0d1d95889cc3b5c","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"30290f210ba7426ff7592fe2eb4114b1b5bad219","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"426384dd4980040651536fef5feac4dcc4d7ee4e","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"},{"lessThan":"50749f2dd6854a41830996ad302aef2ffaf011d8","status":"affected","version":"f214f915e7db99091f1312c48b30928c1e0c90b7","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/core/skbuff.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.14"},{"lessThan":"4.14","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"4.14.*","status":"unaffected","version":"4.14.315","versionType":"semver"},{"lessThanOrEqual":"4.19.*","status":"unaffected","version":"4.19.283","versionType":"semver"},{"lessThanOrEqual":"5.4.*","status":"unaffected","version":"5.4.243","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.180","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.111","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.28","versionType":"semver"},{"lessThanOrEqual":"6.2.*","status":"unaffected","version":"6.2.15","versionType":"semver"},{"lessThanOrEqual":"6.3.*","status":"unaffected","version":"6.3.2","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.4","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"4.14.315","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"4.19.283","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.4.243","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.180","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.111","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.28","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.2.15","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.3.2","versionStartIncluding":"4.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.4","versionStartIncluding":"4.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.\n\nsyzkaller reported [0] memory leaks of an UDP socket and ZEROCOPY\nskbs.  We can reproduce the problem with these sequences:\n\n  sk = socket(AF_INET, SOCK_DGRAM, 0)\n  sk.setsockopt(SOL_SOCKET, SO_TIMESTAMPING, SOF_TIMESTAMPING_TX_SOFTWARE)\n  sk.setsockopt(SOL_SOCKET, SO_ZEROCOPY, 1)\n  sk.sendto(b'', MSG_ZEROCOPY, ('127.0.0.1', 53))\n  sk.close()\n\nsendmsg() calls msg_zerocopy_alloc(), which allocates a skb, sets\nskb->cb->ubuf.refcnt to 1, and calls sock_hold().  Here, struct\nubuf_info_msgzc indirectly holds a refcnt of the socket.  When the\nskb is sent, __skb_tstamp_tx() clones it and puts the clone into\nthe socket's error queue with the TX timestamp.\n\nWhen the original skb is received locally, skb_copy_ubufs() calls\nskb_unclone(), and pskb_expand_head() increments skb->cb->ubuf.refcnt.\nThis additional count is decremented while freeing the skb, but struct\nubuf_info_msgzc still has a refcnt, so __msg_zerocopy_callback() is\nnot called.\n\nThe last refcnt is not released unless we retrieve the TX timestamped\nskb by recvmsg().  Since we clear the error queue in inet_sock_destruct()\nafter the socket's refcnt reaches 0, there is a circular dependency.\nIf we close() the socket holding such skbs, we never call sock_put()\nand leak the count, sk, and skb.\n\nTCP has the same problem, and commit e0c8bccd40fc (\"net: stream:\npurge sk_error_queue in sk_stream_kill_queues()\") tried to fix it\nby calling skb_queue_purge() during close().  However, there is a\nsmall chance that skb queued in a qdisc or device could be put\ninto the error queue after the skb_queue_purge() call.\n\nIn __skb_tstamp_tx(), the cloned skb should not have a reference\nto the ubuf to remove the circular dependency, but skb_clone() does\nnot call skb_copy_ubufs() for zerocopy skb.  So, we need to call\nskb_orphan_frags_rx() for the cloned skb to call skb_copy_ubufs().\n\n[0]:\nBUG: memory leak\nunreferenced object 0xffff88800c6d2d00 (size 1152):\n  comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 cd af e8 81 00 00 00 00  ................\n    02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00  ...@............\n  backtrace:\n    [<0000000055636812>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:2024\n    [<0000000054d77b7a>] sk_alloc+0x3b/0x800 net/core/sock.c:2083\n    [<0000000066f3c7e0>] inet_create net/ipv4/af_inet.c:319 [inline]\n    [<0000000066f3c7e0>] inet_create+0x31e/0xe40 net/ipv4/af_inet.c:245\n    [<000000009b83af97>] __sock_create+0x2ab/0x550 net/socket.c:1515\n    [<00000000b9b11231>] sock_create net/socket.c:1566 [inline]\n    [<00000000b9b11231>] __sys_socket_create net/socket.c:1603 [inline]\n    [<00000000b9b11231>] __sys_socket_create net/socket.c:1588 [inline]\n    [<00000000b9b11231>] __sys_socket+0x138/0x250 net/socket.c:1636\n    [<000000004fb45142>] __do_sys_socket net/socket.c:1649 [inline]\n    [<000000004fb45142>] __se_sys_socket net/socket.c:1647 [inline]\n    [<000000004fb45142>] __x64_sys_socket+0x73/0xb0 net/socket.c:1647\n    [<0000000066999e0e>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n    [<0000000066999e0e>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80\n    [<0000000017f238c1>] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nBUG: memory leak\nunreferenced object 0xffff888017633a00 (size 240):\n  comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    00 00 00 00 00 00 00 00 00 2d 6d 0c 80 88 ff ff  .........-m.....\n  backtrace:\n    [<000000002b1c4368>] __alloc_skb+0x229/0x320 net/core/skbuff.c:497\n    [<00000000143579a6>] alloc_skb include/linux/skbuff.h:1265 [inline]\n    [<00000000143579a6>] sock_omalloc+0xaa/0x190 net/core/sock.c:2596\n    [<00000000be626478>] msg_zerocopy_alloc net/core/skbuff.c:1294 [inline]\n    [<00000000be626478>]\n---truncated---"}],"providerMetadata":{"dateUpdated":"2026-05-11T19:45:58.719Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/281072fb2a7294cde7acbf5375b879f40a8001b7"},{"url":"https://git.kernel.org/stable/c/1f69c086b20e27763af28145981435423f088268"},{"url":"https://git.kernel.org/stable/c/602fa8af44fd55a58f9e94eb673e8adad2c6cc46"},{"url":"https://git.kernel.org/stable/c/230a5ed7d813fb516de81d23f09d7506753e41e9"},{"url":"https://git.kernel.org/stable/c/43e4197dd5f6b474a8b16f8b6a42cd45cf4f9d1a"},{"url":"https://git.kernel.org/stable/c/cb52e7f24c1d01a536a847dff0d1d95889cc3b5c"},{"url":"https://git.kernel.org/stable/c/30290f210ba7426ff7592fe2eb4114b1b5bad219"},{"url":"https://git.kernel.org/stable/c/426384dd4980040651536fef5feac4dcc4d7ee4e"},{"url":"https://git.kernel.org/stable/c/50749f2dd6854a41830996ad302aef2ffaf011d8"}],"title":"tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2023-53489","datePublished":"2025-10-01T11:45:41.304Z","dateReserved":"2025-10-01T11:39:39.403Z","dateUpdated":"2026-11-05T20:31:11.838Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-10-01 12:15:51","lastModifiedDate":"2026-11-05 21:17:23","problem_types":["CWE-401"],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-11-05T20:22:23.206424Z","id":"CVE-2023-53489","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"4.14.315","matchCriteriaId":"BE435BEA-160C-494F-97C6-41FFA86F2943"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"4.19.283","matchCriteriaId":"8AC1BC2D-A61C-4368-A3F6-50DF48E2EFC5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.20","versionEndExcluding":"5.4.243","matchCriteriaId":"E54ACEF5-C8C1-4266-85FC-7D513FFD1DEC"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.180","matchCriteriaId":"78422AC3-CC89-479E-B4BC-62381D8F3564"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.15.111","matchCriteriaId":"2B9DD776-7F17-4F72-B94F-54BFCBC692DD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.28","matchCriteriaId":"08F855F4-7188-4EE1-BD79-D4B6C7E2EF54"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.2.15","matchCriteriaId":"3844A90B-940D-46C3-8D7B-9FF63F1AFC2F"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.3.2","matchCriteriaId":"38F6F330-91A0-4675-8B90-6F950471A7CC"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2023","CveId":"53489","Ordinal":"1","Title":"tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.","CVE":"CVE-2023-53489","Year":"2023"},"notes":[{"CveYear":"2023","CveId":"53489","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp.\n\nsyzkaller reported [0] memory leaks of an UDP socket and ZEROCOPY\nskbs.  We can reproduce the problem with these sequences:\n\n  sk = socket(AF_INET, SOCK_DGRAM, 0)\n  sk.setsockopt(SOL_SOCKET, SO_TIMESTAMPING, SOF_TIMESTAMPING_TX_SOFTWARE)\n  sk.setsockopt(SOL_SOCKET, SO_ZEROCOPY, 1)\n  sk.sendto(b'', MSG_ZEROCOPY, ('127.0.0.1', 53))\n  sk.close()\n\nsendmsg() calls msg_zerocopy_alloc(), which allocates a skb, sets\nskb->cb->ubuf.refcnt to 1, and calls sock_hold().  Here, struct\nubuf_info_msgzc indirectly holds a refcnt of the socket.  When the\nskb is sent, __skb_tstamp_tx() clones it and puts the clone into\nthe socket's error queue with the TX timestamp.\n\nWhen the original skb is received locally, skb_copy_ubufs() calls\nskb_unclone(), and pskb_expand_head() increments skb->cb->ubuf.refcnt.\nThis additional count is decremented while freeing the skb, but struct\nubuf_info_msgzc still has a refcnt, so __msg_zerocopy_callback() is\nnot called.\n\nThe last refcnt is not released unless we retrieve the TX timestamped\nskb by recvmsg().  Since we clear the error queue in inet_sock_destruct()\nafter the socket's refcnt reaches 0, there is a circular dependency.\nIf we close() the socket holding such skbs, we never call sock_put()\nand leak the count, sk, and skb.\n\nTCP has the same problem, and commit e0c8bccd40fc (\"net: stream:\npurge sk_error_queue in sk_stream_kill_queues()\") tried to fix it\nby calling skb_queue_purge() during close().  However, there is a\nsmall chance that skb queued in a qdisc or device could be put\ninto the error queue after the skb_queue_purge() call.\n\nIn __skb_tstamp_tx(), the cloned skb should not have a reference\nto the ubuf to remove the circular dependency, but skb_clone() does\nnot call skb_copy_ubufs() for zerocopy skb.  So, we need to call\nskb_orphan_frags_rx() for the cloned skb to call skb_copy_ubufs().\n\n[0]:\nBUG: memory leak\nunreferenced object 0xffff88800c6d2d00 (size 1152):\n  comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 cd af e8 81 00 00 00 00  ................\n    02 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00  ...@............\n  backtrace:\n    [<0000000055636812>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:2024\n    [<0000000054d77b7a>] sk_alloc+0x3b/0x800 net/core/sock.c:2083\n    [<0000000066f3c7e0>] inet_create net/ipv4/af_inet.c:319 [inline]\n    [<0000000066f3c7e0>] inet_create+0x31e/0xe40 net/ipv4/af_inet.c:245\n    [<000000009b83af97>] __sock_create+0x2ab/0x550 net/socket.c:1515\n    [<00000000b9b11231>] sock_create net/socket.c:1566 [inline]\n    [<00000000b9b11231>] __sys_socket_create net/socket.c:1603 [inline]\n    [<00000000b9b11231>] __sys_socket_create net/socket.c:1588 [inline]\n    [<00000000b9b11231>] __sys_socket+0x138/0x250 net/socket.c:1636\n    [<000000004fb45142>] __do_sys_socket net/socket.c:1649 [inline]\n    [<000000004fb45142>] __se_sys_socket net/socket.c:1647 [inline]\n    [<000000004fb45142>] __x64_sys_socket+0x73/0xb0 net/socket.c:1647\n    [<0000000066999e0e>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n    [<0000000066999e0e>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80\n    [<0000000017f238c1>] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nBUG: memory leak\nunreferenced object 0xffff888017633a00 (size 240):\n  comm \"syz-executor392\", pid 264, jiffies 4294785440 (age 13.044s)\n  hex dump (first 32 bytes):\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n    00 00 00 00 00 00 00 00 00 2d 6d 0c 80 88 ff ff  .........-m.....\n  backtrace:\n    [<000000002b1c4368>] __alloc_skb+0x229/0x320 net/core/skbuff.c:497\n    [<00000000143579a6>] alloc_skb include/linux/skbuff.h:1265 [inline]\n    [<00000000143579a6>] sock_omalloc+0xaa/0x190 net/core/sock.c:2596\n    [<00000000be626478>] msg_zerocopy_alloc net/core/skbuff.c:1294 [inline]\n    [<00000000be626478>]\n---truncated---","Type":"Description","Title":"tcp/udp: Fix memleaks of sk and zerocopy skbs with TX timestamp."}]}}}