{"id":"CVE-2026-62943","summary":"btrbk: SSH Command Filter Bypass in ssh_filter_btrbk.sh","details":"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.","aliases":["GHSA-pf45-7g54-65h5"],"modified":"2026-09-20T11:46:53.940439660Z","published":"2026-09-18T16:24:48.513Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/62xxx/CVE-2026-62943.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-78"]},"references":[{"type":"WEB","url":"https://github.com/digint/btrbk/releases/tag/v0.32.7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/62xxx/CVE-2026-62943.json"},{"type":"ADVISORY","url":"https://github.com/digint/btrbk/security/advisories/GHSA-pf45-7g54-65h5"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-62943"},{"type":"FIX","url":"https://github.com/digint/btrbk/commit/29ca3c093205395bdeb9dd98677ab4139c458aec"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/digint/btrbk","events":[{"introduced":"b64ffbacf5a089df63429b6cd315974213674348"},{"fixed":"29ca3c093205395bdeb9dd98677ab4139c458aec"},{"fixed":"b4676b841865763901712153281de4b1291cedc6"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0.29.0"},{"fixed":"0.32.7"}]}}],"versions":["v0.32.6","v0.32.5","v0.32.4","v0.32.3","v0.32.2","v0.32.1","v0.32.0","v0.31.3","v0.31.2","v0.31.1","v0.31.0","v0.30.0","v0.29.1","v0.29.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-62943.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"}]}