CentOS Linux 8 [TuxCare] Security Update: krb5-devel / krb5-libs / krb5-pkinit / krb5-server / etc Multiple Vulnerabilities (CENTOS-STREAM8:CLSA-2026:1779875639)

high Nessus Plugin ID 351952

Synopsis

The CentOS Linux host is missing one or more security updates.

Description

The CentOS Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare CENTOS-STREAM8:CLSA-2026:1779875639 advisory.

- lib/kadm5/kadm_rpc_xdr.c in MIT Kerberos 5 (aka krb5) before 1.20.2 and 1.21.x before 1.21.1 frees an uninitialized pointer. A remote authenticated user can trigger a kadmind crash. This occurs because
_xdr_kadm5_principal_ent_rec does not validate the relationship between n_key_data and the key_data array count. (CVE-2023-36054)

- In MIT Kerberos 5 (aka krb5) before 1.22 (with incremental propagation), there is an integer overflow for a large update size to resize() in kdb_log.c. An authenticated attacker can cause an out-of-bounds write and kadmind daemon crash. (CVE-2025-24528)

- A vulnerability in the MIT Kerberos implementation allows GSSAPI-protected messages using RC4-HMAC-MD5 to be spoofed due to weaknesses in the MD5 checksum design. If RC4 is preferred over stronger encryption types, an attacker could exploit MD5 collisions to forge message integrity codes. This may lead to unauthorized message tampering. (CVE-2025-3576)

- In MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, causing the process to terminate in parse_nego_message.
(CVE-2026-40355)

- In MIT Kerberos 5 (aka krb5) before 1.22.3, there is an integer underflow and resultant out-of-bounds read if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, possibly causing the process to terminate in parse_message. (CVE-2026-40356)

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

Solution

Update the affected packages based on the guidance in TuxCare advisory CENTOS-STREAM8:CLSA-2026:1779875639.

Plugin Details

Severity: High

ID: 351952

File Name: tuxcare_centos_8_CLSA-2026-1779875639.nasl

Version: 1.1

Type: Local

Agent: unix

Family: CentOS Local Security Checks

Published: 9/30/2026

Updated: 9/30/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 3.9

Percentile: 52.47

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.1

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

CVSS Score Source: CVE-2026-40356

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.7

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:P/RL:O/RC:C

Vulnerability Information

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/27/2026

Vulnerability Publication Date: 9/17/2021

Reference Information

CVE: CVE-2023-36054, CVE-2025-24528, CVE-2025-3576, CVE-2026-40355, CVE-2026-40356

CLSA: 2026:1779875639

Detections

Analytics