Log in Start free

Vulnerability · Published Jul 30, 2026 · Assigned by redhat

CVE-2026-58216Samba: kpasswd service: kpasswd packet that contains malformed asn.1 might cause the server to access 6 bytes of unallocated memory leading server to crash

Medium 5.3

In plain English

A medium-severity out-of-bounds read in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.5%top 59.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12sambano fix listedDEBIAN-CVE-2026-58216
Debian:13samba2:4.22.10+dfsg-0+deb13u2DEBIAN-CVE-2026-58216
Debian:14samba2:4.24.5+dfsg-1DEBIAN-CVE-2026-58216
Ubuntu:22.04:LTSsamba2:4.15.13+dfsg-0ubuntu1.13UBUNTU-CVE-2026-58216
Ubuntu:24.04:LTSsamba2:4.19.5+dfsg-4ubuntu9.7UBUNTU-CVE-2026-58216
Ubuntu:26.04:LTSsamba2:4.23.6+dfsg-1ubuntu2.2UBUNTU-CVE-2026-58216

Affected products (as reported)

VendorProductVersions
Red Hat Red Hat Enterprise Linux 10 see references
Red Hat Red Hat Enterprise Linux 6 see references
Red Hat Red Hat Enterprise Linux 6 see references
Red Hat Red Hat Enterprise Linux 7 see references
Red Hat Red Hat Enterprise Linux 8 see references
Red Hat Red Hat Enterprise Linux 9 see references
Red Hat Red Hat OpenShift Container Platform 4 see references

Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

References