RustFS: Missing admin authorization on /rustfs/admin/v3/metrics allows any authenticated user to read server metrics

Description

RustFS is a distributed object storage system built in Rust. In 1.0.0-beta.7 and earlier, the real-time metrics endpoint at /rustfs/admin/v3/metrics is accessible to any valid IAM user regardless of their assigned policy. Every other admin handler in the codebase calls validate_admin_request to enforce admin-action IAM checks; the MetricsHandler skips this call entirely. A restricted IAM user whose policy grants only access to their own bucket can read server-wide operational metrics including disk I/O statistics, network throughput, scanner cycle timing, and cluster RPC state.

Scores

EPSS (exploitation in 30 days)

0.27% · top 81% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.

Weakness

• CWE-862: Missing Authorization (opens in a new tab)All about CWE-862 and its CVEs

Affected products

• rustfs · rustfs

  • affected <= 1.0.0-beta.7

References (1)

• https://github.com/rustfs/rustfs/security/advisories/GHSA-f5cv-v44x-2xgf (opens in a new tab)x_refsource_CONFIRMexploit

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-55838](https://trackcve.app/badge/CVE-2026-55838.svg)](https://trackcve.app/cve/CVE-2026-55838)

Record last updated 27 Jun 2026, 03:07 UTC.