CVE-2026-58216 Denial of service in Red Hat Enterprise Linux 10
An authenticated attacker can crash the Samba KDC process by sending malformed ASN.1 data, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-58216?
CVE-2026-58216 is a medium-severity denial of service vulnerability in Red Hat Enterprise Linux 10, published on 30 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
An out-of-bounds read flaw was found in Samba's Kerberos Key Distribution Center's (KDC) password change (kpasswd) service. When processing malformed ASN.1-encoded Kerberos password change request, Samba server miscalculates the structure size and attempts to read up to six bytes beyond the end of the allocated buffer. While this out-of-bounds read typically results in a harmless decryption failure, if the read hits unmapped memory, it causes the KDC process to crash. An authenticated attacker can send a specially crafted kpasswd request containing malformed ASN.1 data to trigger the out-of-bounds read, which may cause the KDC process to terminate, resulting in a denial of service.
Weakness: CWE-125
Which versions are affected by CVE-2026-58216?
How do I fix CVE-2026-58216?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-58216 being exploited?
There is no known exploitation of CVE-2026-58216 in the wild and no public exploit code.
Sources
Also known as AZL-94169, DEBIAN-CVE-2026-58216, ECHO-6e23-ce84-c852, GHSA-vc9h-gm8g-6j4x, UBUNTU-CVE-2026-58216.