# CVE-2026-45039

## Summary

- **CVE ID:** CVE-2026-45039
- **Severity:** CRITICAL
- **CVSS Score:** 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** CWE-798, CWE-1392
- **Published:** May 28, 2026
- **Last Modified:** May 30, 2026

## Description

RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-beta.2, the internode RPC layer authenticates every request with an HMAC-SHA256 signature using a shared secret. The function that produces this secret, get_shared_secret() in crates/ecstore/src/rpc/http_auth.rs, falls back to the public, source-tree-embedded DEFAULT_SECRET_KEY = "rustfsadmin" when neither the RUSTFS_RPC_SECRET environment variable nor the global S3 secret key has been configured. This vulnerability is fixed in 1.0.0-beta.2.

## Affected Products

- rustfs — rustfs (< 1.0.0-beta.2)

## References

- [CNA](https://github.com/rustfs/rustfs/security/advisories/GHSA-r5qv-rc46-hv8q)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.27%
- **EPSS Percentile:** 18.8

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._