CVE-2026-62239CWE-59

CVE-2026-62239

Medium · published July 14, 2026

CVSS v3.1
6.6
EPSS
0%
Percentile
5.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.6 · MEDIUM
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00164 · 5.3th percentile
Weakness
CWE-59 · Improper Link Resolution Before File Access ('Link Following')
Published
2026-07-14T02:16Z
References (5)
https://github.com/Dao-AILab/flash-attention/commit/0816ef12f424c6ec94b057a72c275b14f6e6edb2 · [email protected]https://github.com/Dao-AILab/flash-attention/issues/2637 · [email protected]https://github.com/Dao-AILab/flash-attention/pull/2702 · [email protected]https://www.vulncheck.com/advisories/flashattention-symlink-attack-via-tarfile-extractall-in-hopper-setup-py · [email protected]https://github.com/Dao-AILab/flash-attention/issues/2637 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 13 JUL 21:03Z
    FlashAttention Symlink Attack via tarfile.extractall in hopper/setup.py
    cvelistv5