Vulnerability Description
Relative Path Traversal vulnerability in Erlang OTP (stdlib zip module) allows writing files outside the intended extraction directory via a crafted zip archive. zip:unzip/1,2 and zip:extract/1,2 validate entry paths using zip:check_dir_level/2, which tracks directory depth as a running integer counter: .. decrements it, normal path components increment it. The caller rejects only paths where the final counter value is less than zero. A path such as ../x/y causes the counter to go negative mid-traversal then recover to zero, passing validation while resolving to a location outside the extraction directory when joined with the current working directory via add_cwd. This vulnerability is associated with program file lib/stdlib/src/zip.erl. This issue affects OTP from OTP 27.1 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to stdlib from 6.1 before 8.0.3, 7.3.0.1 and 6.2.2.4.
Related Weaknesses (CWE)
References
- https://cna.erlef.org/cves/CVE-2026-47078.html
- https://github.com/erlang/otp/commit/8a933c9c7835b06776d31d17b79b7336627d887a
- https://github.com/erlang/otp/security/advisories/GHSA-rf72-wp7h-jg3x
- https://osv.dev/vulnerability/EEF-CVE-2026-47078
- https://www.erlang.org/doc/system/versions.html#order-of-versions
FAQ
What is CVE-2026-47078?
CVE-2026-47078 is a documented vulnerability. Relative Path Traversal vulnerability in Erlang OTP (stdlib zip module) allows writing files outside the intended extraction directory via a crafted zip archive. zip:unzip/1,2 and zip:extract/1,2 val...
How severe is CVE-2026-47078?
CVSS scoring is not yet available for CVE-2026-47078. Check NVD for updates.
Is there a patch for CVE-2026-47078?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.