CVE-2026-62239

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 v3 6.6 MEDIUM

6.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.3 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/Dao-AILab/flash-attention/commit/0816ef12f424c6ec94b057a72c275b14f6e6edb2
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-extractall-in-hopper-setup-py
https://github.com/Dao-AILab/flash-attention/issues/2637

Configurations

No configuration.

History

14 Jul 2026, 13:19

Type	Values Removed	Values Added
References	~~() https://github.com/Dao-AILab/flash-attention/issues/2637 -~~	() https://github.com/Dao-AILab/flash-attention/issues/2637 -

13 Jul 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-13 22:16

Updated : 2026-07-15 21:02

NVD link : CVE-2026-62239

Mitre link : CVE-2026-62239

CVE.ORG link : CVE-2026-62239

JSON object : View

Products Affected

No product.

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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