CVE-2026-55838

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 4.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 94% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
4.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 4.3Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
4.3
EG Score
4.3(medium)
EPSS
5.7%
KEV
Not listed

Published

June 26, 2026

Last Modified

June 27, 2026

Advisory Details (1)

Auto-updated Jun 26, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Missing admin authorization on /rustfs/admin/v3/metrics allows any authenticated user to read server metrics · Advisory · rustfs/rustfs · GitHub

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

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 16× in last 7d / 49× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-15 16:57 UTCEPSS rescore
  2. 2026-07-15 16:57 UTCEPSS rescore
  3. 2026-07-15 09:03 UTCEG score recompute
  4. 2026-07-14 09:38 UTCEG score recompute
  5. 2026-07-13 22:31 UTCEPSS rescore
  6. 2026-07-13 10:18 UTCEG score recompute
  7. 2026-07-13 06:13 UTCEPSS rescore
  8. 2026-07-13 06:13 UTCEPSS rescore
  9. 2026-07-12 10:59 UTCEG score recompute
  10. 2026-07-11 11:40 UTCEG score recompute
  11. 2026-07-11 08:27 UTCEPSS rescore
  12. 2026-07-11 08:27 UTCEPSS rescore
  13. 2026-07-10 12:22 UTCEG score recompute
  14. 2026-07-09 19:10 UTCEPSS rescore
  15. 2026-07-09 19:10 UTCEPSS rescore
  16. 2026-07-09 13:00 UTCEG score recompute
  17. 2026-07-08 15:16 UTCEPSS rescore
  18. 2026-07-08 15:16 UTCEPSS rescore
  19. 2026-07-08 13:41 UTCEG score recompute
  20. 2026-07-07 14:21 UTCEG score recompute
  21. 2026-07-07 13:46 UTCEPSS rescore
  22. 2026-07-07 13:46 UTCEPSS rescore
  23. 2026-07-06 16:27 UTCEPSS rescore
  24. 2026-07-06 16:27 UTCEPSS rescore
  25. 2026-07-06 14:57 UTCEG score recompute
Show 24 more
  1. 2026-07-06 02:23 UTCEPSS rescore
  2. 2026-07-06 02:23 UTCEPSS rescore
  3. 2026-07-05 15:35 UTCEG score recompute
  4. 2026-07-05 02:31 UTCEPSS rescore
  5. 2026-07-05 02:30 UTCEPSS rescore
  6. 2026-07-04 16:16 UTCEG score recompute
  7. 2026-07-04 06:31 UTCEPSS rescore
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-03 16:58 UTCEG score recompute
  10. 2026-07-02 17:39 UTCEG score recompute
  11. 2026-07-01 18:15 UTCEG score recompute
  12. 2026-07-01 15:07 UTCEPSS rescore
  13. 2026-06-30 23:22 UTCEPSS rescore
  14. 2026-06-30 18:56 UTCEG score recompute
  15. 2026-06-29 19:38 UTCEG score recompute
  16. 2026-06-29 14:06 UTCEPSS rescore
  17. 2026-06-29 14:06 UTCEPSS rescore
  18. 2026-06-28 20:20 UTCEG score recompute
  19. 2026-06-28 14:07 UTCEPSS rescore
  20. 2026-06-28 04:56 UTCEPSS rescore
  21. 2026-06-28 04:56 UTCEPSS rescore
  22. 2026-06-27 21:02 UTCEG score recompute
  23. 2026-06-26 21:43 UTCEG score recompute
  24. 2026-06-26 21:42 UTCNVD updatefirst tracked

Frequently asked(5)

What is CVE-2026-55838?
CVE-2026-55838 is a medium vulnerability published on June 26, 2026. 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 validateadminrequest to…
When was CVE-2026-55838 disclosed?
CVE-2026-55838 was first published in the National Vulnerability Database on June 26, 2026, with the most recent update on June 27, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55838 actively exploited?
CVE-2026-55838 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 5.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-55838?
CVE-2026-55838 has a CVSS v3 base score of 4.3 (NVD).
How do I remediate CVE-2026-55838?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55838, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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