lxc-ci: Pacman keyring stored in archlinux image with a private key
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-321.
Summary
lxc-ci contains continuous integration and image-build scripts for LXC. Prior to the 2026-05-28 Arch Linux image publication, images built from images/archlinux.yaml retain the same pacman local-signing private key in /etc/pacman.d/gnupg and redistribute it to every container or virtual machine created from that image. An attacker who controls an HTTP package mirror or can intercept mirror traffic can use the shared pacman signing private key to sign modified packages that affected clients accept as trusted. Installing those packages permits arbitrary code execution as root on the client system. This issue is fixed in Arch Linux images published on or after 2026-05-28.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA lxc-ci (lxc) Fixed in 2026-05-28
Timeline
- 2026-10-02 Threatist record created from CVE-2026-52727
References
More lxc vulnerabilities
- TI-2019-04061 runc through 1.0-rc6, as used in Docker before 18.09.2 and other products, allows… CVSS 3.1HIGH 8.6
- TI-2026-45063 Incus vulnerable to root RCE via image backup.yaml symlink CVSS 3.1CRITICAL 9.9
- TI-2026-44978 Incus: Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge CVSS 3.1CRITICAL 9.9
- TI-2026-36039 Incus has an arbitrary file write on its client due to trusted image hash CVSS 3.1CRITICAL 9.9
- TI-2026-36024 Incus has an arbitrary file write via path traversal in S3 multipart upload CVSS 3.1CRITICAL 9.9
- TI-2026-36022 Incus has a restricted project bypass leading to arbitrary command execution CVSS 3.1CRITICAL 9.9
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences