{"api_version":"1","generated_at":"2026-08-23T04:03:14+00:00","cve":"CVE-2026-68169","urls":{"html":"https://cve.report/CVE-2026-68169","api":"https://cve.report/api/cve/CVE-2026-68169.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-68169","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68169"},"summary":{"title":"mptcp: pm: userspace: fix use-after-free in get_local_id","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: userspace: fix use-after-free in get_local_id\n\nIn mptcp_pm_userspace_get_local_id(), the address entry is looked up under\nspinlock, but its id is read after dropping the lock. A concurrent deletion\ncan free the entry between the unlock and the read, leading to UAF.\n\nThe race window is narrow. It was reproduced only with a locally\nconstructed stress test that repeatedly overlaps an MP_JOIN SYN with a\nMPTCP_PM_CMD_SUBFLOW_DESTROY request.\n\nHowever, the KASAN report below confirms that the race is reachable:\n\n  [  666.319376] BUG: KASAN: slab-use-after-free in mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319386] Read of size 1 at addr ffff888124845610 by task swapper/0/0\n  ...\n  [  666.319401] Call Trace:\n  [  666.319405]  <IRQ>\n  [  666.319408]  dump_stack_lvl+0x53/0x70\n  [  666.319412]  print_address_description.constprop.0+0x2c/0x3b0\n  [  666.319418]  print_report+0xbe/0x2b0\n  [  666.319421]  ? mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319423]  kasan_report+0xce/0x100\n  [  666.319426]  ? mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319429]  mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319433]  mptcp_pm_get_local_id+0x371/0x440\n  ...\n  [  666.319821] Allocated by task 45539:\n  [  666.319844]  kasan_save_stack+0x33/0x60\n  [  666.319855]  kasan_save_track+0x14/0x30\n  [  666.319858]  __kasan_kmalloc+0x8f/0xa0\n  [  666.319863]  __kmalloc_noprof+0x1e7/0x520\n  [  666.319867]  sock_kmalloc+0xdf/0x130\n  [  666.319885]  sock_kmemdup+0x1b/0x40\n  [  666.319888]  mptcp_userspace_pm_append_new_local_addr+0x261/0x500\n  [  666.319910]  mptcp_pm_nl_announce_doit+0x16a/0x610\n  ...\n  [  666.319967] Freed by task 45560:\n  [  666.319988]  kasan_save_stack+0x33/0x60\n  [  666.319991]  kasan_save_track+0x14/0x30\n  [  666.319994]  kasan_save_free_info+0x3b/0x60\n  [  666.319998]  __kasan_slab_free+0x43/0x70\n  [  666.320000]  kfree+0x166/0x440\n  [  666.320003]  sock_kfree_s+0x1d/0x50\n  [  666.320007]  mptcp_userspace_pm_delete_local_addr.isra.0+0x157/0x200\n  [  666.320011]  mptcp_pm_nl_subflow_destroy_doit+0x51d/0xea0\n\nFix by copying the id into a local variable while still holding the lock,\nand use -1 as a \"not found\" sentinel.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-10 13:20:03","updated_at":"2026-08-17 05:18:17"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/d2c3760b45f2f481a4dd4c5adef4a29dfabd948f","name":"https://git.kernel.org/stable/c/d2c3760b45f2f481a4dd4c5adef4a29dfabd948f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/31ce5af66891f79998fb2e8b8df08e3c98fd72e3","name":"https://git.kernel.org/stable/c/31ce5af66891f79998fb2e8b8df08e3c98fd72e3","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9bc6d5e4ca9f3cbb41d43400b3a31cb0403796c9","name":"https://git.kernel.org/stable/c/9bc6d5e4ca9f3cbb41d43400b3a31cb0403796c9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d64f6c02495f3fad674038cfa7ec049671b59e7b","name":"https://git.kernel.org/stable/c/d64f6c02495f3fad674038cfa7ec049671b59e7b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/40dde4b5d98279471a70e5c8bb713182738c00d9","name":"https://git.kernel.org/stable/c/40dde4b5d98279471a70e5c8bb713182738c00d9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68169","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68169","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ed34dfa19ddbd1e4c85a73636f8cba0211025ea4 d2c3760b45f2f481a4dd4c5adef4a29dfabd948f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f012d796a6de662692159c539689e47e662853a8 31ce5af66891f79998fb2e8b8df08e3c98fd72e3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f012d796a6de662692159c539689e47e662853a8 d64f6c02495f3fad674038cfa7ec049671b59e7b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f012d796a6de662692159c539689e47e662853a8 40dde4b5d98279471a70e5c8bb713182738c00d9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f012d796a6de662692159c539689e47e662853a8 9bc6d5e4ca9f3cbb41d43400b3a31cb0403796c9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e373bfc8ec3d6496ec7e11dd7f4d087a44b1009a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 005a3ad289eb604216dcaa03646de36cb08624a0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.6.18 6.6.151 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.1.79 6.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.7.6 6.8 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.8","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.8 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.151 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.103 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.42 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.6 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"68169","cve":"CVE-2026-68169","epss":"0.002000000","percentile":"0.101670000","score_date":"2026-08-17","updated_at":"2026-08-18 00:11:47"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/mptcp/pm_userspace.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d2c3760b45f2f481a4dd4c5adef4a29dfabd948f","status":"affected","version":"ed34dfa19ddbd1e4c85a73636f8cba0211025ea4","versionType":"git"},{"lessThan":"31ce5af66891f79998fb2e8b8df08e3c98fd72e3","status":"affected","version":"f012d796a6de662692159c539689e47e662853a8","versionType":"git"},{"lessThan":"d64f6c02495f3fad674038cfa7ec049671b59e7b","status":"affected","version":"f012d796a6de662692159c539689e47e662853a8","versionType":"git"},{"lessThan":"40dde4b5d98279471a70e5c8bb713182738c00d9","status":"affected","version":"f012d796a6de662692159c539689e47e662853a8","versionType":"git"},{"lessThan":"9bc6d5e4ca9f3cbb41d43400b3a31cb0403796c9","status":"affected","version":"f012d796a6de662692159c539689e47e662853a8","versionType":"git"},{"status":"affected","version":"e373bfc8ec3d6496ec7e11dd7f4d087a44b1009a","versionType":"git"},{"status":"affected","version":"005a3ad289eb604216dcaa03646de36cb08624a0","versionType":"git"},{"lessThan":"6.6.151","status":"affected","version":"6.6.18","versionType":"semver"},{"lessThan":"6.2","status":"affected","version":"6.1.79","versionType":"semver"},{"lessThan":"6.8","status":"affected","version":"6.7.6","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/mptcp/pm_userspace.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.8"},{"lessThan":"6.8","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.151","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.103","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.42","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.151","versionStartIncluding":"6.6.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.103","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.42","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.6","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"6.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.79","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7.6","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: userspace: fix use-after-free in get_local_id\n\nIn mptcp_pm_userspace_get_local_id(), the address entry is looked up under\nspinlock, but its id is read after dropping the lock. A concurrent deletion\ncan free the entry between the unlock and the read, leading to UAF.\n\nThe race window is narrow. It was reproduced only with a locally\nconstructed stress test that repeatedly overlaps an MP_JOIN SYN with a\nMPTCP_PM_CMD_SUBFLOW_DESTROY request.\n\nHowever, the KASAN report below confirms that the race is reachable:\n\n  [  666.319376] BUG: KASAN: slab-use-after-free in mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319386] Read of size 1 at addr ffff888124845610 by task swapper/0/0\n  ...\n  [  666.319401] Call Trace:\n  [  666.319405]  <IRQ>\n  [  666.319408]  dump_stack_lvl+0x53/0x70\n  [  666.319412]  print_address_description.constprop.0+0x2c/0x3b0\n  [  666.319418]  print_report+0xbe/0x2b0\n  [  666.319421]  ? mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319423]  kasan_report+0xce/0x100\n  [  666.319426]  ? mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319429]  mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319433]  mptcp_pm_get_local_id+0x371/0x440\n  ...\n  [  666.319821] Allocated by task 45539:\n  [  666.319844]  kasan_save_stack+0x33/0x60\n  [  666.319855]  kasan_save_track+0x14/0x30\n  [  666.319858]  __kasan_kmalloc+0x8f/0xa0\n  [  666.319863]  __kmalloc_noprof+0x1e7/0x520\n  [  666.319867]  sock_kmalloc+0xdf/0x130\n  [  666.319885]  sock_kmemdup+0x1b/0x40\n  [  666.319888]  mptcp_userspace_pm_append_new_local_addr+0x261/0x500\n  [  666.319910]  mptcp_pm_nl_announce_doit+0x16a/0x610\n  ...\n  [  666.319967] Freed by task 45560:\n  [  666.319988]  kasan_save_stack+0x33/0x60\n  [  666.319991]  kasan_save_track+0x14/0x30\n  [  666.319994]  kasan_save_free_info+0x3b/0x60\n  [  666.319998]  __kasan_slab_free+0x43/0x70\n  [  666.320000]  kfree+0x166/0x440\n  [  666.320003]  sock_kfree_s+0x1d/0x50\n  [  666.320007]  mptcp_userspace_pm_delete_local_addr.isra.0+0x157/0x200\n  [  666.320011]  mptcp_pm_nl_subflow_destroy_doit+0x51d/0xea0\n\nFix by copying the id into a local variable while still holding the lock,\nand use -1 as a \"not found\" sentinel."}],"providerMetadata":{"dateUpdated":"2026-08-17T05:00:09.840Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d2c3760b45f2f481a4dd4c5adef4a29dfabd948f"},{"url":"https://git.kernel.org/stable/c/31ce5af66891f79998fb2e8b8df08e3c98fd72e3"},{"url":"https://git.kernel.org/stable/c/d64f6c02495f3fad674038cfa7ec049671b59e7b"},{"url":"https://git.kernel.org/stable/c/40dde4b5d98279471a70e5c8bb713182738c00d9"},{"url":"https://git.kernel.org/stable/c/9bc6d5e4ca9f3cbb41d43400b3a31cb0403796c9"}],"title":"mptcp: pm: userspace: fix use-after-free in get_local_id","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-68169","datePublished":"2026-08-10T11:59:38.177Z","dateReserved":"2026-07-30T09:28:09.372Z","dateUpdated":"2026-08-17T05:00:09.840Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-10 13:20:03","lastModifiedDate":"2026-08-17 05:18:17","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"68169","Ordinal":"1","Title":"mptcp: pm: userspace: fix use-after-free in get_local_id","CVE":"CVE-2026-68169","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"68169","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: userspace: fix use-after-free in get_local_id\n\nIn mptcp_pm_userspace_get_local_id(), the address entry is looked up under\nspinlock, but its id is read after dropping the lock. A concurrent deletion\ncan free the entry between the unlock and the read, leading to UAF.\n\nThe race window is narrow. It was reproduced only with a locally\nconstructed stress test that repeatedly overlaps an MP_JOIN SYN with a\nMPTCP_PM_CMD_SUBFLOW_DESTROY request.\n\nHowever, the KASAN report below confirms that the race is reachable:\n\n  [  666.319376] BUG: KASAN: slab-use-after-free in mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319386] Read of size 1 at addr ffff888124845610 by task swapper/0/0\n  ...\n  [  666.319401] Call Trace:\n  [  666.319405]  <IRQ>\n  [  666.319408]  dump_stack_lvl+0x53/0x70\n  [  666.319412]  print_address_description.constprop.0+0x2c/0x3b0\n  [  666.319418]  print_report+0xbe/0x2b0\n  [  666.319421]  ? mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319423]  kasan_report+0xce/0x100\n  [  666.319426]  ? mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319429]  mptcp_userspace_pm_get_local_id+0x1dc/0x1f0\n  [  666.319433]  mptcp_pm_get_local_id+0x371/0x440\n  ...\n  [  666.319821] Allocated by task 45539:\n  [  666.319844]  kasan_save_stack+0x33/0x60\n  [  666.319855]  kasan_save_track+0x14/0x30\n  [  666.319858]  __kasan_kmalloc+0x8f/0xa0\n  [  666.319863]  __kmalloc_noprof+0x1e7/0x520\n  [  666.319867]  sock_kmalloc+0xdf/0x130\n  [  666.319885]  sock_kmemdup+0x1b/0x40\n  [  666.319888]  mptcp_userspace_pm_append_new_local_addr+0x261/0x500\n  [  666.319910]  mptcp_pm_nl_announce_doit+0x16a/0x610\n  ...\n  [  666.319967] Freed by task 45560:\n  [  666.319988]  kasan_save_stack+0x33/0x60\n  [  666.319991]  kasan_save_track+0x14/0x30\n  [  666.319994]  kasan_save_free_info+0x3b/0x60\n  [  666.319998]  __kasan_slab_free+0x43/0x70\n  [  666.320000]  kfree+0x166/0x440\n  [  666.320003]  sock_kfree_s+0x1d/0x50\n  [  666.320007]  mptcp_userspace_pm_delete_local_addr.isra.0+0x157/0x200\n  [  666.320011]  mptcp_pm_nl_subflow_destroy_doit+0x51d/0xea0\n\nFix by copying the id into a local variable while still holding the lock,\nand use -1 as a \"not found\" sentinel.","Type":"Description","Title":"mptcp: pm: userspace: fix use-after-free in get_local_id"}]}}}