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
Affects btrbkSource GCVE Database
Not known to be exploited · CVSS 8.7 High · fixed in 0.32.7 : patch btrbk soon.
Data as of 12 Nov 2026, 20:05 UTC
- Patch
- Available – fixed in 0.32.7
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 18 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10btrbkpkg:deb/ubuntu/btrbk?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSbtrbkpkg:deb/ubuntu/btrbk?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSbtrbkpkg:deb/ubuntu/btrbk?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSbtrbkpkg:deb/ubuntu/btrbk?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSbtrbkpkg:deb/ubuntu/btrbk?arch=source&distro=esm-apps/focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSbtrbkpkg:deb/ubuntu/btrbk?arch=source&distro=esm-apps/bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
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.
References
- ubuntu.com/security/CVE-2026-62943 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-62943 (opens in a new tab)
- github.com/digint/btrbk/security/advisories/GHSA-pf45-7g54-65h5 (opens in a new tab)
- github.com/digint/btrbk/commit/29ca3c093205395bdeb9dd98677ab4139c458aec (opens in a new tab)
- github.com/digint/btrbk/releases/tag/v0.32.7 (opens in a new tab)