CVE Vulnerability

CVE-2021-27851

A security vulnerability that can lead to local privilege escalation has been found in ’guix-daemon’. It affects multi-user setups in which ’guix-daemon’ runs locally. The attack consists in having an unprivileged user spawn a build process, for instance with `guix build`, that makes its build directory world-writable. The user then creates a hardlink to a root-owned file such as /etc/shadow in that build directory. If the user passed the --keep-failed option and the build eventually fails, the daemon changes ownership of the whole build tree, including the hardlink, to the user. At that point, the user has write access to the target file. Versions after and including v0.11.0-3298-g2608e40988, and versions prior to v1.2.0-75109-g94f0312546 are vulnerable.

2.1 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 2.9

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

Scope

5.5 /10

CVSS v3.0 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References
Link Resource
https://guix.gnu.org/en/blog/2021/risk-of-local-privilege-escalation-via-guix-daemon/ Patch Vendor Advisory
https://bugs.gnu.org/47229 Issue Tracking Mailing List
Configurations

Configuration 1

cpe:2.3:a:gnu:guix:*:*:*:*:*:*:*:*
Information

Published : 2021-04-26 04:15

Updated : 2022-07-29 04:34

NVD link : CVE-2021-27851

Mitre link : CVE-2021-27851

Products Affected
No products.
CWE
CWE-59