CVE-2026-62239 (GCVE-0-2026-62239)

Vulnerability from cvelistv5 – Published: 2026-07-13 21:03 – Updated: 2026-07-13 21:03 X_Open Source
VLAI
Title
FlashAttention Symlink Attack via tarfile.extractall in hopper/setup.py
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.
Severity
5.3 (Medium)
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
6.6 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
References
Impacted products
Vendor Product Version
Dao-AILab flash-attention Affected: 0 , ≤ 2.8.3.post1 (custom)
Unaffected: 0816ef12f424c6ec94b057a72c275b14f6e6edb2 (git)
Create a notification for this product.
Date Public
2026-06-09 00:00
Credits
YU SUN
Show details on NVD website
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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