Vulnerability Description
FlashAttention through 2.8.3.post1, fixed in commit 0816ef1, contains a symlink attack vulnerability in the download_and_copy() function within hopper/setup.py that extracts NVIDIA toolchain archives without validating symlinks or filtering tar members. A local attacker can pre-plant a symlink in the predictable cache directory to redirect extracted binaries to an attacker-chosen location, enabling arbitrary file write with victim privileges during build time.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/Dao-AILab/flash-attention/commit/0816ef12f424c6ec94b057a72c27
- https://github.com/Dao-AILab/flash-attention/issues/2637
- https://github.com/Dao-AILab/flash-attention/pull/2702
- https://www.vulncheck.com/advisories/flashattention-symlink-attack-via-tarfile-e
- https://github.com/Dao-AILab/flash-attention/issues/2637
FAQ
What is CVE-2026-62239?
CVE-2026-62239 is a vulnerability with a CVSS score of 6.6 (MEDIUM). FlashAttention through 2.8.3.post1, fixed in commit 0816ef1, contains a symlink attack vulnerability in the download_and_copy() function within hopper/setup.py that extracts NVIDIA toolchain archives ...
How severe is CVE-2026-62239?
CVE-2026-62239 has been rated MEDIUM with a CVSS base score of 6.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-62239?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.