CVE-2026-22043 MEDIUM

CVE-2026-22043: RustFS has IAM deny_only Short-Circuit that Allows Privilege Escalation via Service Account Minting

Vendor Rustfs
Product rustfs
Weakness CWE-269
Published January 8, 2026
Last update January 8, 2026
View on NVD All CVEs

CVSS base score

5.7/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P

What the vulnerability does

01Description

RustFS is a distributed object storage system built in Rust. In versions 1.0.0-alpha.13 through 1.0.0-alpha.78, a flawed `deny_only` short-circuit in RustFS IAM allows a restricted service account or STS credential to self-issue an unrestricted service account, inheriting the parent’s full privileges. This enables privilege escalation and bypass of session/inline policy restrictions. Version 1.0.0-alpha.79 fixes the issue.

Key dates

02Disclosure timeline

January 8, 2026 CVE published
January 8, 2026 Record updated