Bug 2555374

Summary: CVE-2026-16487 containers-common: bootc: automatic updates can apply unsigned mutable-tag content under default containers policy [fedora-all]
Product: [Fedora] Fedora Reporter: Ganesh <gnaik>
Component: containers-commonAssignee: Jan Kaluža <jkaluza>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: bbaude, dwalsh, jkaluza, jnovy, nicola.sella, pholzing, rruzicka, vmiticka
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["8665c692-5950-448a-affe-c6e7bcda6bb7"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-21 05:39:43 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2503686    

Description Ganesh 2026-10-19 05:25:16 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

A flaw was found in RHEL image-mode (bootc) update handling when used with the default containers signature policy. Hosts enrolled to a mutable image tag can automatically fetch and apply updated content for that tag via bootc upgrade / bootc-fetch-apply-updates without signature verification for registries that fall through to insecureAcceptAnything. An attacker who can publish content to the enrolled mutable reference can cause the host to reboot into attacker-controlled OS content running as host root. bootc rollback does not revert persistent /var state written during the malicious deployment window, so naive rollback remediation may leave attacker persistence intact.