CVE-2026-93853
Description
Unverified ownership in Barman snapshot backup deletion allows a principal who can write the backup catalog to cause Barman to delete unrelated cloud snapshots. When a snapshot backup is deleted, either explicitly or by retention policy enforcement, Barman reads the snapshot identifiers from the backup.info file and passes them to the cloud provider's delete API using Barman's own credentials, without verifying that the snapshots belong to that backup. An attacker who can overwrite backup.info but lacks snapshot delete permissions can substitute the identifiers of other snapshots, causing Barman to delete any snapshot its cloud identity can reach on AWS, Microsoft Azure, or Google Cloud. Exploitation requires a deployment where the principal that writes the backup catalog is separate from the identity Barman uses to delete snapshots. Barman versions from 3.4.0 (Google Cloud), 3.6.0 (Azure), and 3.7.0 (AWS) up to and including 3.20.0 are affected. The issue is fixed in Barman 3.20.1.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
CWEs
CWE-283
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.