{"id":"CVE-2026-77206","title":"Libreswan's IKEv2 state machine has a null pointer dereference bug in the EAP handling code for authentication","summary":"Libreswan's IKEv2 state machine has a null pointer dereference bug in the EAP handling code for authentication. As a result of inconsistency within the IKEv2 state machine code, this bug can be triggered by any IKEv2 connection, even if …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-476"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","affected":["fast_datapath_for_rhel 9","enterprise_linux 10","enterprise_linux 8","enterprise_linux 9","openshift_container_platform 4"],"patched":["enterprise_linux_appstream_v_9"],"published":"2026-10-13","updated":"2026-10-16","sourceUpdated":"2026-10-16T19:55:59.740","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-77206","references":[{"url":"https://libreswan.org/security/CVE-2026-77206/","label":"d42dc95b-23f1-4e06-9076-20753a0fb0df"},{"url":"https://libreswan.org/security/CVE-2026-77206/CVE-2026-77206.txt","label":"d42dc95b-23f1-4e06-9076-20753a0fb0df"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77206.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-77206"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2550256"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-77206"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77206"},{"url":"https://libreswan.org/security/CVE-2026-77206/libreswan-5.3-CVE-2026-77206.patch"},{"url":"https://libreswan.org/security/CVE-2026-77206/libreswan-5.4-CVE-2026-77206.patch"},{"url":"https://access.redhat.com/errata/RHSA-2026:89748"}],"tags":["nvd","csaf","vex","red-hat","cve.org"],"epss":0.00658,"epssPercentile":0.51292,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-16T15:14:41.074180Z"},"ingestedAt":"2026-10-13T23:03:54.749Z","slug":"CVE-2026-77206","body":"## Overview\n\nLibreswan's IKEv2 state machine has a null pointer dereference bug in the EAP handling code for authentication. As a result of inconsistency within the IKEv2 state machine code, this bug can be triggered by any IKEv2 connection, even if EAP is not configured at all. The error is caused by a fall-through where it incorrectly dereferences ike->sa.st_eap which is NULL. A malicious IKE_AUTH packet can trigger this bug, meaning the peer does not need to be authenticated. The bug results in a crash and restart of the pluto daemon. No remote code execution is possible. Continued exploitation can cause a denial of service.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Fast Datapath for RHEL 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat OpenShift Container Platform 4 · no fix planned: Fast Datapath for RHEL 9, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat OpenShift Container Platform 4 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77206.json)\n- **RHSA-2026:89748** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-10-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:89748)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}