---
id: CVE-2026-16487
title: >-
  Bootc: containers-common: bootc: automatic updates can apply unsigned
  mutable-tag content under default containers policy
summary: >-
  A flaw was found in bootc when operating with the default containers signature
  policy. Automatic or manual upgrades of a mutable image tag may apply unsigned
  content for registries that fall through to insecureAcceptAnything, allowing
  an…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-345
vendor: Red Hat
product: bootc
affected:
  - bootc (all versions)
  - containers-common (all versions)
  - 'container-tools:rhel8/containers-common (all versions)'
  - bootc (all versions)
  - containers-common (all versions)
  - bootc (all versions)
  - containers-common (all versions)
  - containers-common
  - rhcos
published: '2026-10-19'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T05:27:30.898Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-16487'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-16487'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2503686'
    label: RHBZ#2503686
tags:
  - cve.org
ingestedAt: '2026-10-19T07:09:59.601Z'
---

## Overview

A flaw was found in bootc when operating with the default containers signature policy. Automatic or manual upgrades of a mutable image tag may apply unsigned content for registries that fall through to insecureAcceptAnything, allowing an attacker who can update that tag to execute arbitrary OS content as the host root filesystem on reboot.

## Affected

- `bootc (all versions)`
- `containers-common (all versions)`
- `container-tools:rhel8/containers-common (all versions)`
- `bootc (all versions)`
- `containers-common (all versions)`
- `bootc (all versions)`
- `containers-common (all versions)`
- `containers-common`
- `rhcos`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

### Workarounds

Pin bootc updates to image digests, or configure /etc/containers/policy.json to reject unsigned content by default and allow only explicitly trusted signed scopes. Until policy is hardened, disable automatic updates (bootc-fetch-apply-updates.timer). After a suspected malicious image, do not rely on bootc rollback alone: audit and remediate persistent /var (including /var/roothome), then re-enroll to a trusted signed image.