{"api_version":"1","generated_at":"2026-06-26T03:59:00+00:00","cve":"CVE-2026-53183","urls":{"html":"https://cve.report/CVE-2026-53183","api":"https://cve.report/api/cve/CVE-2026-53183.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-53183","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-53183"},"summary":{"title":"mptcp: allow subflow rcv wnd to shrink","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: allow subflow rcv wnd to shrink\n\nIn MPTCP connection, the `window` field in the TCP header refers to the\nMPTCP-level rcv_nxt and it's right edge should not move backward. Such\nconstraint is enforced at DSS option generation time.\n\nAt the same time, the TCP stack ensures independently that the TCP-level\nrcv wnd right's edge does not move backward. That in turn causes artificial\ninflating of the MPTCP rcv window when the incoming data is acked at the\nTCP level and is OoO in the MPTCP sequence space (or lands in the backlog).\n\nAs a consequence, the incoming traffic can exceed the receiver rcvbuf size\neven when the sender is not misbehaving.\n\nPrevent such scenario forcibly allowing the TCP subflow to shrink the\nTCP-level rcv wnd regardless of the current netns setting.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-06-25 09:16:35","updated_at":"2026-06-25 09:16:35"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/bf364b0f10b27679140699821f88af7f01e2a6e3","name":"https://git.kernel.org/stable/c/bf364b0f10b27679140699821f88af7f01e2a6e3","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/da23be77e1292cd611e736c3aa17da633d7ddce7","name":"https://git.kernel.org/stable/c/da23be77e1292cd611e736c3aa17da633d7ddce7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/653245266913f03fcf21cbca68eed5c197a33e52","name":"https://git.kernel.org/stable/c/653245266913f03fcf21cbca68eed5c197a33e52","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b1fd13074f22105deec45aa02283e322733e0c2d","name":"https://git.kernel.org/stable/c/b1fd13074f22105deec45aa02283e322733e0c2d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c297a4e65c50a2b807d9309b22615080faffa8f3","name":"https://git.kernel.org/stable/c/c297a4e65c50a2b807d9309b22615080faffa8f3","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/aa3861f40ac32706d9e97bfac76984613e278788","name":"https://git.kernel.org/stable/c/aa3861f40ac32706d9e97bfac76984613e278788","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-53183","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53183","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f3589be0c420a3137e5902d15705ced6a36f3f43 bf364b0f10b27679140699821f88af7f01e2a6e3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f3589be0c420a3137e5902d15705ced6a36f3f43 b1fd13074f22105deec45aa02283e322733e0c2d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f3589be0c420a3137e5902d15705ced6a36f3f43 aa3861f40ac32706d9e97bfac76984613e278788 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f3589be0c420a3137e5902d15705ced6a36f3f43 653245266913f03fcf21cbca68eed5c197a33e52 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f3589be0c420a3137e5902d15705ced6a36f3f43 c297a4e65c50a2b807d9309b22615080faffa8f3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected f3589be0c420a3137e5902d15705ced6a36f3f43 da23be77e1292cd611e736c3aa17da633d7ddce7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.19","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.19 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.176 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.143 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.94 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.36 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.13 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"53183","cve":"CVE-2026-53183","epss":"0.001800000","percentile":"0.077680000","score_date":"2026-06-25","updated_at":"2026-06-26 00:06:14"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/mptcp/options.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"bf364b0f10b27679140699821f88af7f01e2a6e3","status":"affected","version":"f3589be0c420a3137e5902d15705ced6a36f3f43","versionType":"git"},{"lessThan":"b1fd13074f22105deec45aa02283e322733e0c2d","status":"affected","version":"f3589be0c420a3137e5902d15705ced6a36f3f43","versionType":"git"},{"lessThan":"aa3861f40ac32706d9e97bfac76984613e278788","status":"affected","version":"f3589be0c420a3137e5902d15705ced6a36f3f43","versionType":"git"},{"lessThan":"653245266913f03fcf21cbca68eed5c197a33e52","status":"affected","version":"f3589be0c420a3137e5902d15705ced6a36f3f43","versionType":"git"},{"lessThan":"c297a4e65c50a2b807d9309b22615080faffa8f3","status":"affected","version":"f3589be0c420a3137e5902d15705ced6a36f3f43","versionType":"git"},{"lessThan":"da23be77e1292cd611e736c3aa17da633d7ddce7","status":"affected","version":"f3589be0c420a3137e5902d15705ced6a36f3f43","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/mptcp/options.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.19"},{"lessThan":"5.19","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.176","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.143","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.94","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.36","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.13","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.176","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.143","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.94","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.36","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.13","versionStartIncluding":"5.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"5.19","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: allow subflow rcv wnd to shrink\n\nIn MPTCP connection, the `window` field in the TCP header refers to the\nMPTCP-level rcv_nxt and it's right edge should not move backward. Such\nconstraint is enforced at DSS option generation time.\n\nAt the same time, the TCP stack ensures independently that the TCP-level\nrcv wnd right's edge does not move backward. That in turn causes artificial\ninflating of the MPTCP rcv window when the incoming data is acked at the\nTCP level and is OoO in the MPTCP sequence space (or lands in the backlog).\n\nAs a consequence, the incoming traffic can exceed the receiver rcvbuf size\neven when the sender is not misbehaving.\n\nPrevent such scenario forcibly allowing the TCP subflow to shrink the\nTCP-level rcv wnd regardless of the current netns setting."}],"providerMetadata":{"dateUpdated":"2026-06-25T08:38:57.443Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/bf364b0f10b27679140699821f88af7f01e2a6e3"},{"url":"https://git.kernel.org/stable/c/b1fd13074f22105deec45aa02283e322733e0c2d"},{"url":"https://git.kernel.org/stable/c/aa3861f40ac32706d9e97bfac76984613e278788"},{"url":"https://git.kernel.org/stable/c/653245266913f03fcf21cbca68eed5c197a33e52"},{"url":"https://git.kernel.org/stable/c/c297a4e65c50a2b807d9309b22615080faffa8f3"},{"url":"https://git.kernel.org/stable/c/da23be77e1292cd611e736c3aa17da633d7ddce7"}],"title":"mptcp: allow subflow rcv wnd to shrink","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-53183","datePublished":"2026-06-25T08:38:57.443Z","dateReserved":"2026-06-09T07:44:35.390Z","dateUpdated":"2026-06-25T08:38:57.443Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-25 09:16:35","lastModifiedDate":"2026-06-25 09:16:35","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"53183","Ordinal":"1","Title":"mptcp: allow subflow rcv wnd to shrink","CVE":"CVE-2026-53183","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"53183","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: allow subflow rcv wnd to shrink\n\nIn MPTCP connection, the `window` field in the TCP header refers to the\nMPTCP-level rcv_nxt and it's right edge should not move backward. Such\nconstraint is enforced at DSS option generation time.\n\nAt the same time, the TCP stack ensures independently that the TCP-level\nrcv wnd right's edge does not move backward. That in turn causes artificial\ninflating of the MPTCP rcv window when the incoming data is acked at the\nTCP level and is OoO in the MPTCP sequence space (or lands in the backlog).\n\nAs a consequence, the incoming traffic can exceed the receiver rcvbuf size\neven when the sender is not misbehaving.\n\nPrevent such scenario forcibly allowing the TCP subflow to shrink the\nTCP-level rcv wnd regardless of the current netns setting.","Type":"Description","Title":"mptcp: allow subflow rcv wnd to shrink"}]}}}