CVE-2026-29790: dbt-common: commonprefix() doesn't protect against path traversal

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-06 · updated 2026-06-17
Weakness: CWE-22

Description

dbt-common is the shared common utilities for dbt-core and adapter implementations use. Prior to versions 1.34.2 and 1.37.3, 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. This issue has been patched in versions 1.34.2 and 1.37.3.

Affected products

dbt-labs dbt-common: before 1.34.2; from 1.35.0 before 1.37.3 — fixed in 1.34.2, 1.37.3

How to fix

Upgrade to a fixed version: dbt-labs dbt-common 1.34.2, 1.37.3. Check the vendor advisory for mitigations.

References

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