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TI-2026-26255 Aliases CVE-2026-33897GHSA-83xr-5xxr-mh92

Incus vulnerable to arbitrary file read and write through pongo templates

Priority MEDIUM 49CWE-1336Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-1336.

Summary

Incus is a system container and virtual machine manager. Prior to version 6.23.0, instance template files can be used to cause arbitrary read or writes as root on the host server. Incus allows for pongo2 templates within instances which can be used at various times in the instance lifecycle to template files inside of the instance. This particular implementation of pongo2 within Incus allowed for file read/write but with the expectation that the pongo2 chroot feature would isolate all such access to the instance's filesystem. This was allowed such that a template could theoretically read a file and then generate a new version of said file. Unfortunately the chroot isolation mechanism is entirely skipped by pongo2 leading to easy access to the entire system's filesystem with root privileges. Version 6.23.0 patches the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00489 42nd percentileScored 2026-11-07
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
None
Automatable
Yes
Technical impact
Total

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-83xr-5xxr-mh92
—github.com/lxc/incus (Go)up to 0.7.0—No fix listedGHSA-83xr-5xxr-mh92
  • 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-83xr-5xxr-mh92
  • github.com/lxc/incus (Go) Vendor— Affected up to 0.7.0 Fixed in — No fix listed GHSA-83xr-5xxr-mh92

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-83xr-5xxr-mh92 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-2026-33897
  2. 2026-10-03 Alias added: GHSA-83xr-5xxr-mh92

References

Advisory 2

Other 2

  • 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