Vulnerability in Rustfs

CVE-2026-21862

RustFS is a distributed object storage system built in Rust. Prior to version alpha.78, IP-based access control can be bypassed: get_condition_values trusts client-supplied X-Forwarded-For/X-Real-Ip without verifying a trusted proxy, so any reachable client can spoof aws:SourceIp and satisfy IP-allowlist policies. This issue has been patched in version alpha.78.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.002 (11.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 11.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-21862: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

  • Rustfs — versions 1.0.0, < alpha.78

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-21862?
CVE-2026-21862 is a high-severity vulnerability in Rustfs, classified under Authentication Bypass by Spoofing. CVSS score: 7.5/10. Published 2026-02-03.
How severe is CVE-2026-21862?
High severity. CVSS v3 base score is 7.5 out of 10.