{"id":"CVE-2026-80586","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: options: reset DSS fields in case of unexpected size\n\nA remote peer could send a malformed DSS with a wrong size, followed by\nanother DSS or MPC + Data","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: options: reset DSS fields in case of unexpected size\n\nA remote peer could send a malformed DSS with a wrong size, followed by\nanother DSS or MPC + Data. In this …","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-824"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 8","enterprise_linux 9","enterprise_linux_baseos_v_8","enterprise_linux_crb_v_8"],"patched":["enterprise_linux_baseos_v_8","enterprise_linux_crb_v_8"],"published":"2026-08-26","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:18:01.740","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80586","references":[{"url":"https://git.kernel.org/stable/c/15e35fdad7a5576bf3f1c8d688877aeb5d1b506b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/192878df582c51d440bf7b91a15f297f29f2b596","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/1fade1b2ac5b1a4948e538fae7313bea57b5ac36","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/26dac5c9ffb20812b475fdf253eb04fab99cff3b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/27ed642a4e7e4b5df4b8522c72c457a67e052493","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/35772b4981f38ba8059372cde8753e8e477e98ec","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4e80eff5c1c893aca2ac1d202f0b256d2e52ecde","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b1256090816ec46011601e084be580731df58fc7","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80586.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-80586"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2524438"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80586"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80586"},{"url":"https://lore.kernel.org/linux-cve-announce/2026082616-CVE-2026-80586-008c@gregkh/T"},{"url":"https://access.redhat.com/errata/RHSA-2026:89083"}],"tags":["nvd","csaf","vex","red-hat","cve.org"],"epss":0.00399,"epssPercentile":0.33956,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T19:17:59.284912Z"},"scores":{"nvd":9.8,"vendor":8.3,"cna":9.8},"ingestedAt":"2026-10-16T19:46:24.312Z","slug":"CVE-2026-80586","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: options: reset DSS fields in case of unexpected size\n\nA remote peer could send a malformed DSS with a wrong size, followed by\nanother DSS or MPC + Data. In this case, the first suboption will be\nignored, but leaving some fields written, which could lead to\ninconsistency or access uninitialized data.\n\nExplicitly reset the fields that could have been modified in case of\nunexpected size.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:89083** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-10-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:89083)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80586.json)","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":230421,"id":"CVE-2026-80586","ts":1793134642603,"field":"cvss","old":"8.3","new":"9.8"},{"seq":230420,"id":"CVE-2026-80586","ts":1793134642603,"field":"severity","old":"high","new":"critical"},{"seq":229360,"id":"CVE-2026-80586","ts":1793019712992,"field":"cvss","old":"9.8","new":"8.3"},{"seq":229359,"id":"CVE-2026-80586","ts":1793019712992,"field":"severity","old":"critical","new":"high"}]}