CVE-2026-45039CWE-1392CWE-798

RustFS: Internode RPC HMAC secret falls back to public default credential, enabling peer impersonation

Critical · published May 28, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
40.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00483 · 40.6th percentile
Weaknesses
CWE-1392 · Use of Default Credentials; CWE-798 · Use of Hard-coded Credentials
Published
2026-05-28T18:39Z
EPSS history
Timeline
  • 28 MAY 18:39Z
    RustFS: Internode RPC HMAC secret falls back to public default credential, enabling peer impersonation
    cvelistv5