23 Oct 2026 15:48:27 UTC
FlashAttention Symlink Attack via tarfile.extractall in hopper/setup.py
cve-program · CVE-2026-62239 · Published
CVE-2026-62239
FlashAttention Symlink Attack via tarfile.extractall in hopper/setup.py
CVSS 4.0 5.3 MEDIUMCVSS 3.1 6.6 MEDIUMCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-62239
PublishedFlashAttention 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.
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