CVE-2026-29790Low▾ Sunlitdbt-common's commonprefix() doesn't protect against path traversal
▾ Sunlit zone — Low / medium · no exploitation signal
impact 13.8 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Exploit-prediction probability, daily snapshots since Jul 13.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
0.3%
Last analysed / modified upstream
What kind of vulnerability is it? Who is impacted?
A path traversal vulnerability exists in dbt-common's safe_extract() function used when extracting tarball archives. The function uses os.path.commonprefix() to validate that extracted files remain within the intended destination directory. However, commonprefix() compares paths character-by-character rather than by path components, allowing a malicious tarball to write files to sibling directories with matching name prefixes.
For example, when extracting to /tmp/packages, a crafted tarball could write files to /tmp/packagesevil/ by exploiting the character-based prefix matching.
This vulnerability affects users who:
The practical risk is limited because:
This is similar to CVE-2026-1703 in pip, which had a CVSS score of 3.9 (Low).
Has the problem been patched? What versions should users upgrade to?
Fixed in dbt-common version 1.37.3 & 1.34.2, and patched for dbt-core 1.11.7 and 1.10.20 releases.
The fix replaces os.path.commonprefix() with os.path.commonpath(), which correctly compares paths by their components rather than characters.
Is there a way for users to fix or remediate the vulnerability without upgrading?
Are there any links users can visit to find out more?
commonpath vs commonprefix: https://docs.python.org/3/library/os.path.html#os.path.commonpathdbt-common < 1.34.2dbt-common >= 1.35.0, < 1.37.3Upgrade to a patched release:
dbt-common 1.34.2dbt-common 1.37.3