Ubuntu update for pam-krb5

1) Buffer overflow

EUVDB-ID: #VU26486

Risk: High

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-10595

CWE-ID: CWE-119 - Memory corruption

Exploit availability: No

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing data passed during supplemental prompting. A remote attacker can pass an overly long string to pam-krb5 via the underlying Kerberos library, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system but requires that the Kerberos library does supplemental prompting, such as with PKINIT or when using the non-standard no_prompt PAM configuration option.

Mitigation

Update the affected packages.

Ubuntu 19.10

libpam-krb5 - 4.8-2ubuntu0.1

Ubuntu 18.04 LTS

libpam-krb5 - 4.8-1ubuntu0.1

Ubuntu 16.04 LTS

libpam-krb5 - 4.7-2ubuntu0.1

Ubuntu 14.04 ESM

libpam-krb5 - 4.6-2ubuntu0.1~esm1

Ubuntu 12.04 ESM

libpam-krb5 - 4.5-3ubuntu0.1

Vulnerable software versions

libpam-krb5 (Ubuntu package): 1.0-2 - 4.8-2

External links

http://www.openwall.com/lists/oss-security/2020/03/31/1
http://github.com/rra/pam-krb5/commit/e7879e27a37119fad4faf133a9f70bdcdc75d760

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.