CVE-2026-58222: Samba: samba ad ldap compare filter injection and trusted-request confusion disclose protected attributes

Vulnerability summary

CVE-2026-58222 is a high (CVSS 8.8) vulnerability in samba. EPSS estimates a 0.80% chance of exploitation in the next 30 days, higher than 56.7% of scored vulnerabilities.

Timeline

1. 30-07-2026
   PublishedVulnerability first disclosed.
2. 30-07-2026
   Last modifiedVulnerability information updated.

Description

A security flaw combining LDAP filter injection and improper authorization checks was found in Samba Active Directory Domain Controller (AD DC). When processing LDAP Compare requests, Samba fails to properly validate user-supplied attribute names and executes the resulting internal database search in a trusted context, bypassing normal Access Control List (ACL) enforcement. An authenticated low-privilege domain user can exploit these flaws to disclose confidential Active Directory attributes that would normally be inaccessible. The disclosed information may be leveraged to derive sensitive authentication material, potentially leading to privilege escalation and complete domain compromise. For example: In deployments configured with Group Managed Service Accounts (gMSAs), an attacker can extract the "msKds-RootKeyData" attribute and derive gMSA passwords offline, potentially leading to complete domain compromise if privileged gMSAs are present.

• CWE-90Improper Neutralization of Special Elements used in an LDAP QueryThe product constructs all or part of an LDAP query using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended LDAP query when it is sent to a downstream component.