Hi,

The following vulnerability was published for btrbk.

CVE-2026-62943[0]:
| btrbk is a tool for creating snapshots and remote backups of Btrfs
| subvolumes. From 0.29.0 until 0.32.7, btrbk's ssh_filter_btrbk.sh
| constructs allow_stream_match with a start anchor but without an
| end-of-string anchor for the complete command. A user restricted
| through an authorized_keys forced command can append a trailing pipe
| command after a valid btrbk command prefix, bypassing the allowlist
| and executing arbitrary commands with the privileges of the backup-
| target SSH account. Deployments that do not use ssh_filter_btrbk.sh
| in authorized_keys are not affected. This issue is fixed in version
| 0.32.7.

https://github.com/digint/btrbk/security/advisories/GHSA-pf45-7g54-65h5
https://github.com/digint/btrbk/commit/29ca3c093205395bdeb9dd98677ab4139c458aec (v0.32.7)


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-62943
https://www.cve.org/CVERecord?id=CVE-2026-62943

Please adjust the affected versions in the BTS as needed.