CVE-2021-27851 is a local privilege escalation vulnerability in guix-daemon, affecting multi-user setups of GNU Guix versions between v0.11.0-3298-g2608e40988 and v1.2.0-75109-g94f0312546. An unprivileged user can create a world-writable build directory, hardlink a root-owned file like /etc/shadow, and if the build fails with --keep-failed, the daemon changes ownership of the hardlink, granting the user write access to the target file. This vulnerability has a CVSS score of 5.5 (Medium), indicating low attack complexity and local access requirements, with a high impact on integrity. There is no evidence of active exploitation, public exploit code, or significant community discussion, with its EPSS score being very low.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 0.11.0, < 1.2.0CPE matchmatch criteria | cpe:2.3:a:gnu:guix:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
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The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.