---
cve: "CVE-2026-62239"
severity: "MEDIUM"
cvss: 5.3
epss: "0.2%"
vendor: "Dao-AILab"
kev: false
exploited: false
published: "2026-07-13 22:16:51"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-21T04:02:16+02:00"
---

# CVE-2026-62239

> 5.3 MEDIUM · 🧪 PoC

## Beschreibung

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-Vektor

```
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
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |

## Patch verfügbar (OSV)

- a8aa52b1ab3e9ca574c8a33b3f35afc017ffa2e2 (Commit)
- 0816ef12f424c6ec94b057a72c275b14f6e6edb2 (Commit)

## Referenzen

- <https://github.com/Dao-AILab/flash-attention/issues/2637>
- <https://github.com/Dao-AILab/flash-attention/pull/2702>
- <https://github.com/Dao-AILab/flash-attention/commit/0816ef12f424c6ec94b057a72c275b14f6e6edb2>
- <https://www.vulncheck.com/advisories/flashattention-symlink-attack-via-tarfile-extractall-in-hopper-setup-py>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-62239) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_