PT-2026-35666 · Mit+1 · Mit Kerberos 5+1

Cem Onat Karagun · Published 2026-04-28 · Updated 2026-05-27 · CVE-2026-40356

Positive Technologies (AI Summary)

CVSS v3.1

5.9

Medium

Base vector

AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions MIT Kerberos 5 versions prior to 1.22.3

Description An integer underflow leads to an out-of-bounds read when an application calls the gss accept sec context() function on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this issue, which may cause the process to terminate in parse message(). An integer underflow occurs when a subtraction results in a value smaller than the minimum representable value for that data type, often wrapping around to a very large positive number.

Recommendations Update to version 1.22.3 or later.

Fix

DoS

Integer Underflow

Weakness Enumeration

CWE-191

Related Identifiers

ALSA-2026:16799

ALSA-2026:19145

ALSA-2026:19357

CVE-2026-40356

ECHO-874C-29E0-D62B

OESA-2026-2257

OPENSUSE-SU-2026:10729-1

RHSA-2026:19145

RHSA-2026:19357

Affected Products

Mit Kerberos 5

Rocky Linux

References · 39

• https://ubuntu.com/security/CVE-2026-40356 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10729-1 · Vendor Advisory
• https://osv.dev/vulnerability/ALSA-2026:19145 · Vendor Advisory
• https://errata.rockylinux.org/RLSA-2026:16799 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-13-CVE-2026-40356 · Vendor Advisory
• https://errata.rockylinux.org/RLSA-2026:19357 · Vendor Advisory
• https://linux.oracle.com/errata/ELSA-2026-16799.html · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-12-CVE-2026-40356 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-40356 · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-40356 · Vendor Advisory
• https://errata.almalinux.org/10/ALSA-2026-19145.html · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-40356 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-40356 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-40355 · Security Note
• https://osv.dev/vulnerability/ALSA-2026:19357 · Vendor Advisory