CVE-2026-27905

BentoML is a Python library for building online serving systems optimized for AI apps and model inference. Prior to 1.4.36, the safe_extract_tarfile() function validates that each tar member's path is within the destination directory, but for symlink members it only validates the symlink's own path, not the symlink's target. An attacker can create a malicious bento/model tar file containing a symlink pointing outside the extraction directory, followed by a regular file that writes through the symlink, achieving arbitrary file write on the host filesystem. This vulnerability is fixed in 1.4.36.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bentoml/BentoML/commit/4e0eb007765ac04c7924220d643f264715cc9670	Patch
https://github.com/bentoml/BentoML/security/advisories/GHSA-m6w7-qv66-g3mf	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:bentoml:bentoml:*:*:*:*:*:*:*:*

History

05 Mar 2026, 21:04

Type	Values Removed	Values Added
CPE		cpe:2.3:a:bentoml:bentoml::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.8
First Time		Bentoml Bentoml bentoml
References	~~() https://github.com/bentoml/BentoML/commit/4e0eb007765ac04c7924220d643f264715cc9670 -~~	() https://github.com/bentoml/BentoML/commit/4e0eb007765ac04c7924220d643f264715cc9670 - Patch
References	~~() https://github.com/bentoml/BentoML/security/advisories/GHSA-m6w7-qv66-g3mf -~~	() https://github.com/bentoml/BentoML/security/advisories/GHSA-m6w7-qv66-g3mf - Exploit, Mitigation, Vendor Advisory

03 Mar 2026, 23:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-03 23:15

Updated : 2026-03-05 21:04

NVD link : CVE-2026-27905

Mitre link : CVE-2026-27905

CVE.ORG link : CVE-2026-27905

JSON object : View

Products Affected

bentoml

bentoml

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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