CVE-2020-10595 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

http://www.openwall.com/lists/oss-security/2020/03/31/1 https://github.com/rra/pam-krb5/commit/e7879e27a37119fad4faf133a9f70bdcdc75d760 https://lists.debian.org/debian-lts-announce/2020/04/msg00000.html https://usn.ubuntu.com/4314-1/ https://www.debian.org/security/2020/dsa-4648 https://www.eyrie.org/~eagle/software/pam-krb5/security/2020-03-30.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8