Incus has Nil-Pointer Dereference via S3 Bucket Import

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-41647: 0.39% estimated exploitation activity in the next 30 days; percentile 33.69 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Missing error handling could lead an authenticated Incus user to cause a daemon crash through the import of a truncated storage bucket backup file. Details It was found that TransferManager.UploadAllFiles iterates over tar entries but only checks for io.EOF from tr.Next(). When tr.Next() returns a non-EOF error, such as unexpected EOF from a truncated archive, the header hdr is nil and the code continues to access hdr.Name, causing a nil-pointer dereference that panics the daemon. This may allow the Incus daemon to be crashed during S3 bucket restore if a truncated or corrupted backup archive is provided. A panic can occur when a malformed archive produces a non-EOF tar read error after the first entry. Any caller of UploadAllFiles that processes attacker-controlled archive content may be affected. Affected File: https://github.com/lxc/incus/blob/v6.22.0/…server/storage/s3/transfermanager.go#L127 The tar-iteration loop only checks for EOF: Affected Code: When tr.Next()…

Published by the source

4 May 2026, 19:38 UTC

Last modified by the source

8 May 2026, 21:47 UTC

Source last checked

26 Oct 2026, 15:20 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-fwj8-62r8-8p8m

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-41647

Advisory: Incus has Nil-Pointer Dereference via S3 Bucket Import
IDs: CVE-2026-41647, GHSA-fwj8-62r8-8p8m
Record: https://patchnext.com/advisories/cve-2026-41647 (revision 1, source checked 26 Oct 2026, 15:20 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/lxc/incus/v6/cmd/incusd: affected <= 6.23.0

## Suggested inspection (read-only)
- Go github.com/lxc/incus/v6/cmd/incusd: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/lxc/incus/v6/cmd/incusd.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-fwj8-62r8-8p8m (GitHub-reviewed advisory GHSA-fwj8-62r8-8p8m lists affected ranges: Go github.com/lxc/incus/v6/cmd/incusd >=0 <=6.23.0)

Commands are suggestions: review each one before running it.