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TI-2026-26090 Aliases CVE-2026-33711GHSA-q9vp-3wcg-8p4x

Incus vulnerable to local privilege escalation through VM screenshot path

Priority MEDIUM 55CWE-61Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00364 30th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed incus (lxc): 6.23.0github.com/lxc/incus/v6 (Go): 6.23.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
lxcincusbefore 6.23.06.23.0Patch availableCNA
—github.com/lxc/incus/v6 (Go)before 6.23.06.23.0Patch availableGHSA-q9vp-3wcg-8p4x
  • incus Vendorlxc Affected before 6.23.0 Fixed in 6.23.0 Patch available CNA
  • github.com/lxc/incus/v6 (Go) Vendor— Affected before 6.23.0 Fixed in 6.23.0 Patch available GHSA-q9vp-3wcg-8p4x

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*before 6.23.0Vulnerablelxc
  • cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:* Versions before 6.23.0 Vulnerable ·lxc

Remediation

  • Fix · CNA incus (lxc) Fixed in 6.23.0
  • Fix · GHSA-q9vp-3wcg-8p4x github.com/lxc/incus/v6 (Go) Fixed in 6.23.0 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33711
  2. 2026-10-03 Alias added: GHSA-q9vp-3wcg-8p4x

References

Exploit 1

Advisory 1

Other 3

  • TI-2026-19296 Incus container image templating arbitrary host file read and write CVSS 3.1HIGH 8.7
  • TI-2026-19295 Incus container environment configuration newline injection CVSS 3.1HIGH 8.7
  • TI-2025-39899 Incus vulnerable to local privilege escalation through custom storage volumes CVSS 4.0HIGH 8.6
  • TI-2026-29045 Incus out-of-bounds panic in snapshot metadata handling allows denial of service CVSS 4.0HIGH 7.1
  • TI-2026-29009 Incus nil-pointer dereference in storage bucket import allows denial of service CVSS 4.0HIGH 7.1
  • TI-2026-26122 Incus vulnerable to denial of source through crafted bucket backup file CVSS 3.1MEDIUM 6.5
See all 17 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences