CVE-2026-33711

Name
CVE-2026-33711
Description
Incus is a system container and virtual machine manager. Incus provides an API to retrieve VM screenshots. That API relies on the use of a temporary file for QEMU to write the screenshot to which is then picked up and sent to the user prior to deletion. As versions prior to 6.23.0 use predictable paths under /tmp for this, an attacker with local access to the system can abuse this mechanism by creating their own symlinks ahead of time. On the vast majority of Linux systems, this will result in a "Permission denied" error when requesting a screenshot. That's because the Linux kernel has a security feature designed to block such attacks, `protected_symlinks`. On the rare systems with this purposefully disabled, it's then possible to trick Incus intro truncating and altering the mode and permissions of arbitrary files on the filesystem, leading to a potential denial of service or possible local privilege escalation. Version 6.23.0 fixes the issue.
NVD Severity
unknown
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
security-advisories@github.com https://github.com/lxc/incus/security/advisories/GHSA-q9vp-3wcg-8p4x

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:* incus >= None < 6.23.0

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
incus edge-community 6.0.6-r1 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.6-r0 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r9 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r8 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r7 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r6 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r5 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r4 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r3 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r2 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r1 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.5-r0 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.4-r5 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.4-r4 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.4-r3 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.4-r2 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.4-r1 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.4-r0 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.3-r4 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.3-r3 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.3-r2 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.3-r1 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.3-r0 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus edge-community 6.0.2-r0 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.6-r1 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.6-r0 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.5-r8 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.5-r7 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.5-r6 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.5-r5 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable
incus 3.23-community 6.0.5-r4 Leonardo Arena <rnalrd@alpinelinux.org> possibly vulnerable