CVE-2026-31253
The flash-attention training framework thru commit e724e2588cbe754beb97cf7c011b5e7e34119e62 (2025-13-04) contains an insecure deserialization vulnerability (CWE-502) in its checkpoint loading mechanism. The load_checkpoint() function in checkpoint.py and the checkpoint loading code in eval.py use torch.load() without enabling the security-restrictive weights_only=True parameter. This allows the deserialization of arbitrary Python objects via the pickle module. An attacker can exploit this by providing a maliciously crafted checkpoint file. When a victim loads this checkpoint during model warmstarting or evaluation, arbitrary code is executed on the victim's system.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- Puntuación base: 7.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.37%
- Percentil entre todas las CVEs puntuadas: 29
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access92 % - Impacto principal
T1059Command and Scripting Interpreterexecution95 % - Impacto secundario
T1068Exploitation for Privilege Escalationprivilege escalation65 %
Red sin autenticación (AV:N, PR:N) requiere interacción mínima: cargar checkpoint. Deserialización pickle permite ejecución arbitrary code (T1059). Potencial escalada si se ejecuta con privilegios elevados.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-94, CWE-502
Referencias
JSON original (NVD)
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"id": "CVE-2026-31253",
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"id": "CVE-2026-31253",
"role": "CISA Coordinator",
"options": [
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"version": "2.0.3",
"timestamp": "2026-05-12T19:32:06.944533Z"
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"integrityImpact": "LOW",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "LOW",
"privilegesRequired": "NONE",
"confidentialityImpact": "LOW"
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"affected": [
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"published": "2026-05-11T17:16:20.307",
"references": [
{
"url": "https://github.com/Dao-AILab/flash-attention",
"source": "cve@mitre.org"
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{
"url": "https://www.notion.so/CVE-2026-31253-35d1e1393188813f9e77e2038104bc49",
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"vulnStatus": "Deferred",
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"value": "The flash-attention training framework thru commit e724e2588cbe754beb97cf7c011b5e7e34119e62 (2025-13-04) contains an insecure deserialization vulnerability (CWE-502) in its checkpoint loading mechanism. The load_checkpoint() function in checkpoint.py and the checkpoint loading code in eval.py use torch.load() without enabling the security-restrictive weights_only=True parameter. This allows the deserialization of arbitrary Python objects via the pickle module. An attacker can exploit this by providing a maliciously crafted checkpoint file. When a victim loads this checkpoint during model warmstarting or evaluation, arbitrary code is executed on the victim's system."
}
],
"lastModified": "2026-06-17T10:33:32.820",
"sourceIdentifier": "cve@mitre.org"
}