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Fencer Intel
high 7.5

CVE-2026-77207 json

Null Pointer Dereference in PKCS#7 bundle with no certificates

published 29d ago modified 26d ago also EUVD-2026-100749

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits
0
none known

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_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.

Patch / fix

  • The Libreswan Project libreswan 5.3.3, 5.4.1
  • libreswan AlmaLinux 9 4.15-11.el9_8
  • libreswan AlmaLinux 10 5.3.3-1.el10_2
  • libreswan-minimal AlmaLinux 10 5.3.3-1.el10_2
  • libreswan AlmaLinux 8 4.12-2.el8_10.7

almalinux advisories ALSA-2026:89748ALSA-2026:89923ALSA-2026:90492

  • libreswan Rocky Linux 9 4.15-11.el9_8
  • libreswan Rocky Linux 8 4.12-2.el8_10.7
  • libreswan Rocky Linux 10 5.3.3-1.el10_2

rocky linux advisories RLSA-2026:97878RLSA-2026:90492RLSA-2026:89923RLSA-2026:89748

  • libreswan Alpine 3.24, Alpine 3.23 5.3.3-r0

alpine advisories ALPINE-CVE-2026-77207

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • libreswan Azure Linux 3.0 4.15-4

azure linux advisories AZL-108033

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-77207 updated cvss 7.5

libreswan: Null Pointer Dereference in PKCS#7 bundle with no CERTS

  • Red Hat OpenShift Container Platform 4 libreswan
    affected: workaround, no fix available
  • Red Hat Fast Datapath for Red Hat Enterprise Linux 9 libreswan 5.3.3-3.el9fdp
    fixed: vendor fix RHSA-2026:98046
  • Red Hat Enterprise Linux AppStream (v. 8) libreswan 4.12-2.el8_10.7
    fixed: vendor fix RHSA-2026:90492
  • Red Hat Enterprise Linux AppStream (v. 9) libreswan 4.15-11.el9_8, libreswan 4.15-11.el9_9
    fixed: vendor fix RHSA-2026:89748
  • Red Hat Enterprise Linux AppStream (v. 10) libreswan 5.3.3-1.el10_2, libreswan 5.4.1-1.el10_3, libreswan-minimal 5.3.3-1.el10_2, libreswan-minimal 5.4.1-1.el10_3
    fixed: vendor fix RHSA-2026:89923
  • Red Hat OpenShift Container Platform 4.22 rhcos 4.22.9.8.202611032353
    fixed: vendor fix RHSA-2026:95346
  • Red Hat OpenShift Container Platform 5.0 rhcos 5.0.9.8.202611022248, rhcos 5.0.10.2.202611022203
    fixed: vendor fix RHSA-2026:94537
  • Red Hat Enterprise Linux 6 libreswan Red Hat Enterprise Linux 7 libreswan
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
26d ago

Exploit prediction

0.46% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • The Libreswan Project libreswan

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.