{"api_version":"1","generated_at":"2026-09-26T04:27:25+00:00","cve":"CVE-2026-80588","urls":{"html":"https://cve.report/CVE-2026-80588","api":"https://cve.report/api/cve/CVE-2026-80588.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-80588","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-80588"},"summary":{"title":"mptcp: reclaim forward-allocated memory on RX path errors","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: reclaim forward-allocated memory on RX path errors\n\nAfter commit 9db5b3cec4ec (\"mptcp: borrow forward memory from subflow\"),\nerrors in the receive path prior to queueing skbs into the receive\nqueue do not trigger forward-allocated memory reclaiming.\n\nPrevent forward memory from growing unboundedly in pathological drop\nscenarios by explicitly reclaiming memory when skbs are dropped.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-26 15:17:15","updated_at":"2026-08-27 06:17:46"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"baseScore":7.5,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/8277f48a06d3aa1441f6d0b6998ccc0360d30ed8","name":"https://git.kernel.org/stable/c/8277f48a06d3aa1441f6d0b6998ccc0360d30ed8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/473f1a5ab2abc98dd9e74b95b9c23c66c47535cc","name":"https://git.kernel.org/stable/c/473f1a5ab2abc98dd9e74b95b9c23c66c47535cc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/41b49a8b914ec7dcb03eae93fb27f3c464078644","name":"https://git.kernel.org/stable/c/41b49a8b914ec7dcb03eae93fb27f3c464078644","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80588","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80588","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a84164847b1e0a106ebc46821e5d2f9b775c9dc8 473f1a5ab2abc98dd9e74b95b9c23c66c47535cc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9db5b3cec4ec1c0cd3239689f5c8653d691a1754 8277f48a06d3aa1441f6d0b6998ccc0360d30ed8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9db5b3cec4ec1c0cd3239689f5c8653d691a1754 41b49a8b914ec7dcb03eae93fb27f3c464078644 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18.35 6.18.46 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.19","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.46 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.10 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":"80588","cve":"CVE-2026-80588","epss":"0.003390000","percentile":"0.264780000","score_date":"2026-08-27","updated_at":"2026-08-28 00:03:39"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/mptcp/protocol.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"473f1a5ab2abc98dd9e74b95b9c23c66c47535cc","status":"affected","version":"a84164847b1e0a106ebc46821e5d2f9b775c9dc8","versionType":"git"},{"lessThan":"8277f48a06d3aa1441f6d0b6998ccc0360d30ed8","status":"affected","version":"9db5b3cec4ec1c0cd3239689f5c8653d691a1754","versionType":"git"},{"lessThan":"41b49a8b914ec7dcb03eae93fb27f3c464078644","status":"affected","version":"9db5b3cec4ec1c0cd3239689f5c8653d691a1754","versionType":"git"},{"lessThan":"6.18.46","status":"affected","version":"6.18.35","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/mptcp/protocol.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.19"},{"lessThan":"6.19","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.46","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.10","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":"6.18.46","versionStartIncluding":"6.18.35","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.10","versionStartIncluding":"6.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"6.19","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: reclaim forward-allocated memory on RX path errors\n\nAfter commit 9db5b3cec4ec (\"mptcp: borrow forward memory from subflow\"),\nerrors in the receive path prior to queueing skbs into the receive\nqueue do not trigger forward-allocated memory reclaiming.\n\nPrevent forward memory from growing unboundedly in pathological drop\nscenarios by explicitly reclaiming memory when skbs are dropped."}],"metrics":[{"cvssV3_1":{"baseScore":7.5,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:N - Remote TCP/MPTCP peers reach the bug on the established-connection RX datapath (tcp_rcv_established → subflow_data_ready → mptcp_data_ready → __mptcp_move_skbs_from_subflow → __mptcp_move_skb → mptcp_drop) when duplicate or out-of-window mapped data is dropped before skb_set_owner_r().\nAC:L - The attacker fully controls subflow packet contents and ordering on their MPTCP connection and can deterministically trigger drops (duplicate map_seq, OoO beyond rcv_wnd) on every crafted segment without races, rare sysctl state, or uncontrollable memory layout.\nPR:N - No local account or kernel capability is required on the victim; any remote peer that completes the TCP/MPTCP handshake on an IPPROTO_MPTCP socket (Android clients, MPTCP-enabled servers, curl --mptcp) can flood pathological RX drops without target credentials.\nUI:N - Exploitation needs only attacker-generated MPTCP/TCP traffic on an existing or attacker-initiated connection; no victim mount, file open, click, or other cooperative user action beyond normal network stack processing.\nS:U - Impact is unbounded sk_forward_alloc growth and kernel memory exhaustion on the affected host; it does not cross VM, container, IOMMU, or sandbox boundaries to another security authority.\nC:N - This is a forward-memory accounting leak on skb drop after mptcp_borrow_fwdmem(); skb data is freed and no use-after-free, out-of-bounds read, or other memory-corruption primitive exposes kernel contents to the attacker.\nI:N - The flaw only fails to reclaim borrowed forward allocation when dropping skbs; it does not corrupt, overwrite, or modify attacker-chosen memory and provides no write or code-execution primitive.\nA:H - Each pre-queue drop leaks roughly skb->truesize forward memory while bypassing the removed sk_rmem_schedule guard, so a remote peer can repeatedly trigger unbounded per-connection kernel memory growth and OOM denial of service, matching CNA precedent for repeatable network skb/memory leaks."}]}],"providerMetadata":{"dateUpdated":"2026-08-27T05:02:09.335Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/473f1a5ab2abc98dd9e74b95b9c23c66c47535cc"},{"url":"https://git.kernel.org/stable/c/8277f48a06d3aa1441f6d0b6998ccc0360d30ed8"},{"url":"https://git.kernel.org/stable/c/41b49a8b914ec7dcb03eae93fb27f3c464078644"}],"title":"mptcp: reclaim forward-allocated memory on RX path errors","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-80588","datePublished":"2026-08-26T14:37:42.685Z","dateReserved":"2026-08-26T14:34:25.770Z","dateUpdated":"2026-08-27T05:02:09.335Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-26 15:17:15","lastModifiedDate":"2026-08-27 06:17:46","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"80588","Ordinal":"1","Title":"mptcp: reclaim forward-allocated memory on RX path errors","CVE":"CVE-2026-80588","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"80588","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: reclaim forward-allocated memory on RX path errors\n\nAfter commit 9db5b3cec4ec (\"mptcp: borrow forward memory from subflow\"),\nerrors in the receive path prior to queueing skbs into the receive\nqueue do not trigger forward-allocated memory reclaiming.\n\nPrevent forward memory from growing unboundedly in pathological drop\nscenarios by explicitly reclaiming memory when skbs are dropped.","Type":"Description","Title":"mptcp: reclaim forward-allocated memory on RX path errors"}]}}}