Division by zero in Linux kernel - CVE-2026-89550
Published: September 12, 2026
Vulnerability identifier: #VU149255
CSH Severity: Medium
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89550
CWE-ID: CWE-369
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to improper input validation in svcauth_gss_unwrap_priv() when handling a crafted short krb5 token. A remote user can send a crafted token that triggers a division by zero to cause a denial of service.
The issue affects krb5 v2 contexts.
Affected software
Linux kernel
How to mitigate CVE-2026-89550
Install security update from vendor's repository.