{"api_version":"1","generated_at":"2026-09-25T14:33:25+00:00","cve":"CVE-2026-97566","urls":{"html":"https://cve.report/CVE-2026-97566","api":"https://cve.report/api/cve/CVE-2026-97566.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-97566","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-97566"},"summary":{"title":"mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: kernel: drop pending ADD_ADDR when removing ID0\n\nThe in-kernel MPTCP path manager can leave a stale ADD_ADDR announcement\nentry alive when removing the id 0 endpoint. This happens because the id 0\nremoval path does not tear down pending announcements, unlike the non-zero\nid path.\n\nWhen the PM later reselects id 0 after adding another signal endpoint, it\nfinds the stale anno_list entry and hits WARN_ON_ONCE(mptcp_pm_is_kernel())\nin mptcp_pm_announced_alloc().\n\nRoot cause: asymmetry between removal paths.\n- Non-zero id path: mptcp_nl_remove_subflow_and_signal_addr() calls\n  mptcp_pm_remove_announced() to clean up.\n- Id 0 path: mptcp_nl_remove_id_zero_address() skips cleanup entirely.\n\nFix by making the id 0 path symmetric: call mptcp_pm_announced_remove()\nand decrement add_addr_signaled before queuing the RM_ADDR.\n\nSubtle detail: signal endpoints are stored in anno_list with port 0, but\nmsk_local carries the connection's local port. In other words, entries\nlinked to ID0 paths should have port == 0. A follow-up patch will ensure\nthat. mptcp_pm_announced_remove() uses use_port=true for comparison. So\nclear the port before the lookup.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:07","updated_at":"2026-09-25 11:17:07"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/2ac7d6e620764f1fc79eb4edd3610a7a661981ca","name":"https://git.kernel.org/stable/c/2ac7d6e620764f1fc79eb4edd3610a7a661981ca","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d4a67a880654e1bfe318a31bea0bdbb026a09ade","name":"https://git.kernel.org/stable/c/d4a67a880654e1bfe318a31bea0bdbb026a09ade","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/545616b4e7325be3c61fc082538cb06d14f7b1db","name":"https://git.kernel.org/stable/c/545616b4e7325be3c61fc082538cb06d14f7b1db","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97566","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97566","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 740d798e8767d8a449902b1a1bbc70facfce19b5 d4a67a880654e1bfe318a31bea0bdbb026a09ade git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 740d798e8767d8a449902b1a1bbc70facfce19b5 545616b4e7325be3c61fc082538cb06d14f7b1db git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 740d798e8767d8a449902b1a1bbc70facfce19b5 2ac7d6e620764f1fc79eb4edd3610a7a661981ca git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.13","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.13 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.53 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/mptcp/pm_kernel.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d4a67a880654e1bfe318a31bea0bdbb026a09ade","status":"affected","version":"740d798e8767d8a449902b1a1bbc70facfce19b5","versionType":"git"},{"lessThan":"545616b4e7325be3c61fc082538cb06d14f7b1db","status":"affected","version":"740d798e8767d8a449902b1a1bbc70facfce19b5","versionType":"git"},{"lessThan":"2ac7d6e620764f1fc79eb4edd3610a7a661981ca","status":"affected","version":"740d798e8767d8a449902b1a1bbc70facfce19b5","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/mptcp/pm_kernel.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.13"},{"lessThan":"5.13","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.53","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.53","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"5.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc3","versionStartIncluding":"5.13","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: kernel: drop pending ADD_ADDR when removing ID0\n\nThe in-kernel MPTCP path manager can leave a stale ADD_ADDR announcement\nentry alive when removing the id 0 endpoint. This happens because the id 0\nremoval path does not tear down pending announcements, unlike the non-zero\nid path.\n\nWhen the PM later reselects id 0 after adding another signal endpoint, it\nfinds the stale anno_list entry and hits WARN_ON_ONCE(mptcp_pm_is_kernel())\nin mptcp_pm_announced_alloc().\n\nRoot cause: asymmetry between removal paths.\n- Non-zero id path: mptcp_nl_remove_subflow_and_signal_addr() calls\n  mptcp_pm_remove_announced() to clean up.\n- Id 0 path: mptcp_nl_remove_id_zero_address() skips cleanup entirely.\n\nFix by making the id 0 path symmetric: call mptcp_pm_announced_remove()\nand decrement add_addr_signaled before queuing the RM_ADDR.\n\nSubtle detail: signal endpoints are stored in anno_list with port 0, but\nmsk_local carries the connection's local port. In other words, entries\nlinked to ID0 paths should have port == 0. A follow-up patch will ensure\nthat. mptcp_pm_announced_remove() uses use_port=true for comparison. So\nclear the port before the lookup."}],"providerMetadata":{"dateUpdated":"2026-09-25T10:21:53.068Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d4a67a880654e1bfe318a31bea0bdbb026a09ade"},{"url":"https://git.kernel.org/stable/c/545616b4e7325be3c61fc082538cb06d14f7b1db"},{"url":"https://git.kernel.org/stable/c/2ac7d6e620764f1fc79eb4edd3610a7a661981ca"}],"title":"mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-97566","datePublished":"2026-09-25T10:21:53.068Z","dateReserved":"2026-09-24T16:01:01.155Z","dateUpdated":"2026-09-25T10:21:53.068Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:07","lastModifiedDate":"2026-09-25 11:17:07","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"97566","Ordinal":"1","Title":"mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0","CVE":"CVE-2026-97566","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"97566","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: pm: kernel: drop pending ADD_ADDR when removing ID0\n\nThe in-kernel MPTCP path manager can leave a stale ADD_ADDR announcement\nentry alive when removing the id 0 endpoint. This happens because the id 0\nremoval path does not tear down pending announcements, unlike the non-zero\nid path.\n\nWhen the PM later reselects id 0 after adding another signal endpoint, it\nfinds the stale anno_list entry and hits WARN_ON_ONCE(mptcp_pm_is_kernel())\nin mptcp_pm_announced_alloc().\n\nRoot cause: asymmetry between removal paths.\n- Non-zero id path: mptcp_nl_remove_subflow_and_signal_addr() calls\n  mptcp_pm_remove_announced() to clean up.\n- Id 0 path: mptcp_nl_remove_id_zero_address() skips cleanup entirely.\n\nFix by making the id 0 path symmetric: call mptcp_pm_announced_remove()\nand decrement add_addr_signaled before queuing the RM_ADDR.\n\nSubtle detail: signal endpoints are stored in anno_list with port 0, but\nmsk_local carries the connection's local port. In other words, entries\nlinked to ID0 paths should have port == 0. A follow-up patch will ensure\nthat. mptcp_pm_announced_remove() uses use_port=true for comparison. So\nclear the port before the lookup.","Type":"Description","Title":"mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0"}]}}}