{"api_version":"1","generated_at":"2026-04-19T01:12:29+00:00","cve":"CVE-2026-23458","urls":{"html":"https://cve.report/CVE-2026-23458","api":"https://cve.report/api/cve/CVE-2026-23458.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-23458","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-23458"},"summary":{"title":"netfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct()\n\nctnetlink_dump_exp_ct() stores a conntrack pointer in cb->data for the\nnetlink dump callback ctnetlink_exp_ct_dump_table(), but drops the\nconntrack reference immediately after netlink_dump_start().  When the\ndump spans multiple rounds, the second recvmsg() triggers the dump\ncallback which dereferences the now-freed conntrack via nfct_help(ct),\nleading to a use-after-free on ct->ext.\n\nThe bug is that the netlink_dump_control has no .start or .done\ncallbacks to manage the conntrack reference across dump rounds.  Other\ndump functions in the same file (e.g. ctnetlink_get_conntrack) properly\nuse .start/.done callbacks for this purpose.\n\nFix this by adding .start and .done callbacks that hold and release the\nconntrack reference for the duration of the dump, and move the\nnfct_help() call after the cb->args[0] early-return check in the dump\ncallback to avoid dereferencing ct->ext unnecessarily.\n\n BUG: KASAN: slab-use-after-free in ctnetlink_exp_ct_dump_table+0x4f/0x2e0\n Read of size 8 at addr ffff88810597ebf0 by task ctnetlink_poc/133\n\n CPU: 1 UID: 0 PID: 133 Comm: ctnetlink_poc Not tainted 7.0.0-rc2+ #3 PREEMPTLAZY\n Call Trace:\n  <TASK>\n  ctnetlink_exp_ct_dump_table+0x4f/0x2e0\n  netlink_dump+0x333/0x880\n  netlink_recvmsg+0x3e2/0x4b0\n  ? aa_sk_perm+0x184/0x450\n  sock_recvmsg+0xde/0xf0\n\n Allocated by task 133:\n  kmem_cache_alloc_noprof+0x134/0x440\n  __nf_conntrack_alloc+0xa8/0x2b0\n  ctnetlink_create_conntrack+0xa1/0x900\n  ctnetlink_new_conntrack+0x3cf/0x7d0\n  nfnetlink_rcv_msg+0x48e/0x510\n  netlink_rcv_skb+0xc9/0x1f0\n  nfnetlink_rcv+0xdb/0x220\n  netlink_unicast+0x3ec/0x590\n  netlink_sendmsg+0x397/0x690\n  __sys_sendmsg+0xf4/0x180\n\n Freed by task 0:\n  slab_free_after_rcu_debug+0xad/0x1e0\n  rcu_core+0x5c3/0x9c0","state":"PUBLISHED","assigner":"Linux","published_at":"2026-04-03 16:16:32","updated_at":"2026-04-18 09:16:28"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/9821b47f669eb82791fa0b1a6ebaf9aa219bea72","name":"https://git.kernel.org/stable/c/9821b47f669eb82791fa0b1a6ebaf9aa219bea72","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/04c8907ce4e3d3e26c5e1a3e47aa5d17082cbb56","name":"https://git.kernel.org/stable/c/04c8907ce4e3d3e26c5e1a3e47aa5d17082cbb56","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bdf2724eefd4455a66863abb025bab8d3aa98c57","name":"https://git.kernel.org/stable/c/bdf2724eefd4455a66863abb025bab8d3aa98c57","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5cb81eeda909dbb2def209dd10636b51549a3f8a","name":"https://git.kernel.org/stable/c/5cb81eeda909dbb2def209dd10636b51549a3f8a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f04cc86d59906513d2d62183b882966fc0ae0390","name":"https://git.kernel.org/stable/c/f04cc86d59906513d2d62183b882966fc0ae0390","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/cd541f15b60e2257441398cf495d978f816d09f8","name":"https://git.kernel.org/stable/c/cd541f15b60e2257441398cf495d978f816d09f8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d8cd0efbccc5cfb0a80da744a7da76e1333ab925","name":"https://git.kernel.org/stable/c/d8cd0efbccc5cfb0a80da744a7da76e1333ab925","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f025171feef2ac65663d7986f1d5ff0c28d6b2a9","name":"https://git.kernel.org/stable/c/f025171feef2ac65663d7986f1d5ff0c28d6b2a9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-23458","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23458","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 d8cd0efbccc5cfb0a80da744a7da76e1333ab925 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 9821b47f669eb82791fa0b1a6ebaf9aa219bea72 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 bdf2724eefd4455a66863abb025bab8d3aa98c57 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 f04cc86d59906513d2d62183b882966fc0ae0390 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 f025171feef2ac65663d7986f1d5ff0c28d6b2a9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 04c8907ce4e3d3e26c5e1a3e47aa5d17082cbb56 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 cd541f15b60e2257441398cf495d978f816d09f8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e844a928431fa8f1359d1f4f2cef53d9b446bf52 5cb81eeda909dbb2def209dd10636b51549a3f8a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3.10","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 3.10 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.253 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.203 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.167 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.130 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.78 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.20 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.10 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"23458","cve":"CVE-2026-23458","epss":"0.000320000","percentile":"0.090980000","score_date":"2026-04-18","updated_at":"2026-04-19 00:10:43"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/netfilter/nf_conntrack_netlink.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d8cd0efbccc5cfb0a80da744a7da76e1333ab925","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"9821b47f669eb82791fa0b1a6ebaf9aa219bea72","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"bdf2724eefd4455a66863abb025bab8d3aa98c57","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"f04cc86d59906513d2d62183b882966fc0ae0390","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"f025171feef2ac65663d7986f1d5ff0c28d6b2a9","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"04c8907ce4e3d3e26c5e1a3e47aa5d17082cbb56","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"cd541f15b60e2257441398cf495d978f816d09f8","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"},{"lessThan":"5cb81eeda909dbb2def209dd10636b51549a3f8a","status":"affected","version":"e844a928431fa8f1359d1f4f2cef53d9b446bf52","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/netfilter/nf_conntrack_netlink.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"3.10"},{"lessThan":"3.10","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.253","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.203","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.167","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.130","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.78","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.20","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.253","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.203","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.167","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.130","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.78","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.20","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.10","versionStartIncluding":"3.10","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"3.10","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct()\n\nctnetlink_dump_exp_ct() stores a conntrack pointer in cb->data for the\nnetlink dump callback ctnetlink_exp_ct_dump_table(), but drops the\nconntrack reference immediately after netlink_dump_start().  When the\ndump spans multiple rounds, the second recvmsg() triggers the dump\ncallback which dereferences the now-freed conntrack via nfct_help(ct),\nleading to a use-after-free on ct->ext.\n\nThe bug is that the netlink_dump_control has no .start or .done\ncallbacks to manage the conntrack reference across dump rounds.  Other\ndump functions in the same file (e.g. ctnetlink_get_conntrack) properly\nuse .start/.done callbacks for this purpose.\n\nFix this by adding .start and .done callbacks that hold and release the\nconntrack reference for the duration of the dump, and move the\nnfct_help() call after the cb->args[0] early-return check in the dump\ncallback to avoid dereferencing ct->ext unnecessarily.\n\n BUG: KASAN: slab-use-after-free in ctnetlink_exp_ct_dump_table+0x4f/0x2e0\n Read of size 8 at addr ffff88810597ebf0 by task ctnetlink_poc/133\n\n CPU: 1 UID: 0 PID: 133 Comm: ctnetlink_poc Not tainted 7.0.0-rc2+ #3 PREEMPTLAZY\n Call Trace:\n  <TASK>\n  ctnetlink_exp_ct_dump_table+0x4f/0x2e0\n  netlink_dump+0x333/0x880\n  netlink_recvmsg+0x3e2/0x4b0\n  ? aa_sk_perm+0x184/0x450\n  sock_recvmsg+0xde/0xf0\n\n Allocated by task 133:\n  kmem_cache_alloc_noprof+0x134/0x440\n  __nf_conntrack_alloc+0xa8/0x2b0\n  ctnetlink_create_conntrack+0xa1/0x900\n  ctnetlink_new_conntrack+0x3cf/0x7d0\n  nfnetlink_rcv_msg+0x48e/0x510\n  netlink_rcv_skb+0xc9/0x1f0\n  nfnetlink_rcv+0xdb/0x220\n  netlink_unicast+0x3ec/0x590\n  netlink_sendmsg+0x397/0x690\n  __sys_sendmsg+0xf4/0x180\n\n Freed by task 0:\n  slab_free_after_rcu_debug+0xad/0x1e0\n  rcu_core+0x5c3/0x9c0"}],"providerMetadata":{"dateUpdated":"2026-04-18T08:59:08.175Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d8cd0efbccc5cfb0a80da744a7da76e1333ab925"},{"url":"https://git.kernel.org/stable/c/9821b47f669eb82791fa0b1a6ebaf9aa219bea72"},{"url":"https://git.kernel.org/stable/c/bdf2724eefd4455a66863abb025bab8d3aa98c57"},{"url":"https://git.kernel.org/stable/c/f04cc86d59906513d2d62183b882966fc0ae0390"},{"url":"https://git.kernel.org/stable/c/f025171feef2ac65663d7986f1d5ff0c28d6b2a9"},{"url":"https://git.kernel.org/stable/c/04c8907ce4e3d3e26c5e1a3e47aa5d17082cbb56"},{"url":"https://git.kernel.org/stable/c/cd541f15b60e2257441398cf495d978f816d09f8"},{"url":"https://git.kernel.org/stable/c/5cb81eeda909dbb2def209dd10636b51549a3f8a"}],"title":"netfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-23458","datePublished":"2026-04-03T15:15:39.041Z","dateReserved":"2026-01-13T15:37:46.021Z","dateUpdated":"2026-04-18T08:59:08.175Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-03 16:16:32","lastModifiedDate":"2026-04-18 09:16:28","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"23458","Ordinal":"1","Title":"netfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_c","CVE":"CVE-2026-23458","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"23458","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_ct()\n\nctnetlink_dump_exp_ct() stores a conntrack pointer in cb->data for the\nnetlink dump callback ctnetlink_exp_ct_dump_table(), but drops the\nconntrack reference immediately after netlink_dump_start().  When the\ndump spans multiple rounds, the second recvmsg() triggers the dump\ncallback which dereferences the now-freed conntrack via nfct_help(ct),\nleading to a use-after-free on ct->ext.\n\nThe bug is that the netlink_dump_control has no .start or .done\ncallbacks to manage the conntrack reference across dump rounds.  Other\ndump functions in the same file (e.g. ctnetlink_get_conntrack) properly\nuse .start/.done callbacks for this purpose.\n\nFix this by adding .start and .done callbacks that hold and release the\nconntrack reference for the duration of the dump, and move the\nnfct_help() call after the cb->args[0] early-return check in the dump\ncallback to avoid dereferencing ct->ext unnecessarily.\n\n BUG: KASAN: slab-use-after-free in ctnetlink_exp_ct_dump_table+0x4f/0x2e0\n Read of size 8 at addr ffff88810597ebf0 by task ctnetlink_poc/133\n\n CPU: 1 UID: 0 PID: 133 Comm: ctnetlink_poc Not tainted 7.0.0-rc2+ #3 PREEMPTLAZY\n Call Trace:\n  <TASK>\n  ctnetlink_exp_ct_dump_table+0x4f/0x2e0\n  netlink_dump+0x333/0x880\n  netlink_recvmsg+0x3e2/0x4b0\n  ? aa_sk_perm+0x184/0x450\n  sock_recvmsg+0xde/0xf0\n\n Allocated by task 133:\n  kmem_cache_alloc_noprof+0x134/0x440\n  __nf_conntrack_alloc+0xa8/0x2b0\n  ctnetlink_create_conntrack+0xa1/0x900\n  ctnetlink_new_conntrack+0x3cf/0x7d0\n  nfnetlink_rcv_msg+0x48e/0x510\n  netlink_rcv_skb+0xc9/0x1f0\n  nfnetlink_rcv+0xdb/0x220\n  netlink_unicast+0x3ec/0x590\n  netlink_sendmsg+0x397/0x690\n  __sys_sendmsg+0xf4/0x180\n\n Freed by task 0:\n  slab_free_after_rcu_debug+0xad/0x1e0\n  rcu_core+0x5c3/0x9c0","Type":"Description","Title":"netfilter: ctnetlink: fix use-after-free in ctnetlink_dump_exp_c"}]}}}