Pam Krb5
CVE-2020-10595
CRITICAL
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
1DescriptionNVD
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.
AnalysisAI
pam-krb5 before 4.9 has a buffer overflow that might cause remote code execution in situations involving supplemental prompting by a Kerberos library. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
Technical ContextAI
This vulnerability is classified as Buffer Copy without Size Check (CWE-120), which allows attackers to overflow a buffer to corrupt adjacent memory. 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 include: Pam-Krb5 Project Pam-Krb5, Debian Debian Linux. Version information: before 4.9.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Always validate buffer sizes before copy operations. Use bounded functions (strncpy, snprintf). Enable compiler protections.
Same weakness CWE-120 – Classic Buffer Overflow
View allSame technique Buffer Overflow
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External POC / Exploit Code
Leaving vuln.today