CVE-2020-10595: Debian Linux

Critical severity, CVSS 9.8. EPSS: 4.8% chance of exploitation in the next 30 days.

pam-krb5 before 4.9 has a buffer overflow that might cause remote code execution in situations involving supplemental prompting by a Kerberos library. It may overflow a buffer provided by the underlying Kerberos library by a single '\0' byte if an attacker responds to a prompt with an answer of a carefully chosen length. The effect may range from heap corruption to stack corruption depending on the structure of the underlying Kerberos library, with unknown effects but possibly including code execution. This code path is not used for normal authentication, but only when the Kerberos library does supplemental prompting, such as with PKINIT or when using the non-standard no_prompt PAM configuration option.

Affected products

• Debian Debian Linux: version 8.0 only; version 9.0 only; version 10.0 only
• Pam-KRB5 Project Pam-KRB5: before 4.9 (fixed in 4.9)

Published 2020-03-31. Last modified 2026-06-17.