MIT Kerberos 5 GSSAPI-protected Message weak hash

Summaryinfo

A vulnerability classified as problematic has been found in MIT Kerberos 5. This vulnerability affects unknown code of the component GSSAPI-protected Message Handler. This manipulation causes weak hash. This vulnerability is handled as CVE-2025-3576. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in MIT Kerberos 5 (version now known) and classified as problematic. Affected by this vulnerability is some unknown processing of the component GSSAPI-protected Message Handler. The manipulation with an unknown input leads to a weak hash vulnerability. The CWE definition for the vulnerability is CWE-328. The product uses an algorithm that produces a digest (output value) that does not meet security expectations for a hash function that allows an adversary to reasonably determine the original input (preimage attack), find another input that can produce the same hash (2nd preimage attack), or find multiple inputs that evaluate to the same hash (birthday attack). As an impact it is known to affect integrity. The summary by CVE is:

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.

The advisory is shared at access.redhat.com. This vulnerability is known as CVE-2025-3576 since 04/14/2025. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/23/2025). MITRE ATT&CK project uses the attack technique T1600.001 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 237586 (Debian dla-4195 : krb5-admin-server - security update), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (237586), EUVD (EUVD-2025-10925) and CERT Bund (WID-SEC-2025-0795). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• MIT Kerberos
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM MQ
• NetApp ActiveIQ Unified Manager
• IBM QRadar SIEM
• IBM App Connect Enterprise

Productinfo

Type

• Network Authentication Software

Vendor

• MIT

Name

• Kerberos 5

License

• open-source

Website

• Vendor: http://www.mit.edu/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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