AlmaLinux 9.2 [TuxCare] Security Update: libreswan (ALMALINUX9.2:CLSA-2026:1792158739)

high Nessus Plugin ID 366645

Synopsis

The AlmaLinux host is missing one or more security updates.

Description

The AlmaLinux 9.2 host has a package installed that is affected by a vulnerability as referenced in the TuxCare ALMALINUX9.2:CLSA-2026:1792158739 advisory.

- 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. (CVE-2026-77207)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected libreswan package based on the guidance in TuxCare advisory ALMALINUX9.2:CLSA-2026:1792158739.

See Also

https://cve.tuxcare.com/els/releases/CLSA-2026:1792158739

http://www.nessus.org/u?2b202005

Plugin Details

Severity: High

ID: 366645

File Name: tuxcare_alma_linux_9.2_CLSA-2026-1792158739.nasl

Version: 1.1

Type: Local

Published: 10/16/2026

Updated: 10/16/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.67

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2026-77207

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/AlmaLinux/release, Host/AlmaLinux/rpm-list, Host/OS/extended-third-party

Exploit Ease: No known exploits are available

Patch Publication Date: 10/16/2026

Vulnerability Publication Date: 10/13/2026

Reference Information

CVE: CVE-2026-77207

CLSA: 2026:1792158739