CVE-2025-3576

A vulnerability in the MIT Kerberos implementation allows GSSAPI-protected messages using RC4-HMAC-MD5 to be spoofed due to weaknesses in the MD5 checksum design. If RC4 is preferred over stronger encryption types, an attacker could exploit MD5 collisions to forge message integrity codes. This may lead to unauthorized message tampering.

This issue is classified as a moderate severity vulnerability because it affects the handling of PKINIT requests during ASN.1 decoding in krb5. Exploitation requires specific and uncommon configurations, including a Kerberos environment with PKINIT enabled. Additionally, successful exploitation depends on triggering specific memory allocation failures or parser behaviors, contributing to a high attack complexity.The attack requires that PKINIT is actively configured and in use, and cannot be exploited remotely without this setup in place, making the practical risk limited in standard environments.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.