---
id: CVE-2026-77207
title: >-
  Libreswan has a null pointer dereference bug in the PKCS#7 handling code for
  IKE certificate authentication
summary: >-
  Libreswan has a null pointer dereference bug in the PKCS#7 handling code for
  IKE certificate authentication. When libreswan decodes an IKE CERT payload of
  type CERT_PKCS7_WRAPPED_X509, it guards the PKCS#7 blob with
  SEC_PKCS7ContainsCert…
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-252
  - 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-2026-77207'
references:
  - url: 'https://libreswan.org/security/CVE-2026-77207/'
    label: d42dc95b-23f1-4e06-9076-20753a0fb0df
  - url: 'https://libreswan.org/security/CVE-2026-77207/CVE-2026-77207.txt'
    label: d42dc95b-23f1-4e06-9076-20753a0fb0df
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77207.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-77207'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2550258'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-77207'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77207'
  - url: >-
      https://libreswan.org/security/CVE-2026-77207/libreswan-5.3-CVE-2026-77207.patch
  - url: >-
      https://libreswan.org/security/CVE-2026-77207/libreswan-5.4-CVE-2026-77207.patch
  - url: 'https://access.redhat.com/errata/RHSA-2026:89748'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00463
epssPercentile: 0.39929
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-16T15:14:50.209248Z'
ingestedAt: '2026-10-13T23:03:54.749Z'
---

## Overview

Libreswan has a null pointer dereference bug in the PKCS#7 handling code for IKE certificate authentication. When libreswan decodes an IKE CERT payload of type CERT_PKCS7_WRAPPED_X509, it guards the PKCS#7 blob with SEC_PKCS7ContainsCertsOrCrls() and then iterates the certificate list with SEC_PKCS7GetCertificateList(). The two NSS APIs disagree on a SignedData that carries a CRL but no certificates: ContainsCertsOrCrls() returns PR_TRUE (there is a CRL), so the guard passes, but GetCertificateList() returns NULL (there are no certificates). This causes libreswan to dereference a null pointer leading to a crash and restart. A malicious IKE_AUTH packet can trigger this bug, meaning the peer does not need to be authenticated. No remote code execution is possible. Continued exploitation can cause a denial of service.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **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-2026-77207.json)
- **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)