CVE-2026-62239 | FlashAttention through 2.8.3.post1, fixed in commit 0816ef1,… | CVSS 6.6 MEDIUM

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.

Metadata

CVE ID: CVE-2026-62239
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-07-13 16:41 UTC
Published: 2026-07-13 21:03 UTC
Last updated: 2026-07-13 21:03 UTC
Primary CWE: CWE-59
Improper Link Resolution Before File Access ('Link Following…
Vendor / Product: Dao-AILab / flash-attention
Sources: cve.org · NVD

Severity & Metrics

6.6 MEDIUM CVSS 3.1

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

Affected products (1)

Vendor	Product	Platform	Versions
Dao-AILab	flash-attention	—	0 ≤ 2.8.3.post1, 0816ef12f424c6ec94b057a72c275b14f6e6edb2

Weakness (CWE)

CWE	Source	Description
CWE-59	cna	Improper Link Resolution Before File Access ('Link Following')

CVSS scores (2)

Score	Severity	Version	Source	Vector
6.6	MEDIUM	3.1	cna	CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
5.3	MEDIUM	4.0	cna	CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

References (4)