CVE-2026-62239

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Dao-AILabflash-attention0 <= 2.8.3.post1affected
Dao-AILabflash-attention0816ef12f424c6ec94b057a72c275b14f6e6edb2unaffected

Weaknesses

  • CWE-59: Improper Link Resolution Before File Access ('Link Following')

References