{"id":"CVE-2026-80993","title":"kernel: net: phylink: correctly validate returned PCS in phylink_inband_caps (CVE-2026-80993)","summary":"A flaw was found in the Linux kernel's `net: phylink` component. The `phylink_inband_caps()` function does not correctly validate the return value from `mac_select_pcs`, which can return an error pointer instead of a valid Physical Coding …","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-476","vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 9","openshift_container_platform 4"],"published":"2026-09-11","updated":"2026-09-14","sourceUpdated":"2026-09-14T20:06:39+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80993.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80993.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-80993"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532314"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80993"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80993"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-80993.mbox"},{"url":"https://git.kernel.org/stable/c/b6b533f83461c3730875cf3ed5ff6362dcb67be9"},{"url":"https://git.kernel.org/stable/c/fb4d77553841ae85bed9b2cf03351c401e871d85"},{"url":"https://git.kernel.org/stable/c/f2849b1fd059ec9b3281b771e6ac5aad9feee851"}],"tags":["csaf","vex","red-hat","cve.org"],"epss":0.00166,"epssPercentile":0.06249,"ingestedAt":"2026-09-14T00:35:28.531Z","slug":"CVE-2026-80993","body":"## Overview\n\nA flaw was found in the Linux kernel's `net: phylink` component. The `phylink_inband_caps()` function does not correctly validate the return value from `mac_select_pcs`, which can return an error pointer instead of a valid Physical Coding Sublayer (PCS) object. This oversight can lead to dereferencing an invalid pointer, causing a kernel panic. A kernel panic results in a system crash, leading to a Denial of Service (DoS).\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80993.json)\n\n**kernel: net: phylink: correctly validate returned PCS in phylink_inband_caps** — rated Low by Red Hat. Released 2026-09-11, updated 2026-09-14.\n\nAffected:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNo fix planned:\n\n- Red Hat Enterprise Linux 10\n- Red Hat Enterprise Linux 9\n- Red Hat OpenShift Container Platform 4\n\nNot affected:\n\n- Red Hat Enterprise Linux 6\n- Red Hat Enterprise Linux 7\n- Red Hat Enterprise Linux 8\n- Red Hat OpenShift Container Platform 4\n\n## Remediation\n\nFix deferred","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":204152,"id":"CVE-2026-80993","ts":1789490233685,"field":"cvss","old":null,"new":"5.5"},{"seq":204151,"id":"CVE-2026-80993","ts":1789490233685,"field":"severity","old":"none","new":"medium"},{"seq":147389,"id":"CVE-2026-80993","ts":1789270210712,"field":"cvss","old":null,"new":"4.1"},{"seq":147388,"id":"CVE-2026-80993","ts":1789270210712,"field":"severity","old":"none","new":"medium"},{"seq":109147,"id":"CVE-2026-80993","ts":1789183730493,"field":"cvss","old":null,"new":"4.1"},{"seq":109146,"id":"CVE-2026-80993","ts":1789183730493,"field":"severity","old":"none","new":"medium"}]}