CVE-2026-45039
RustFS: Internode RPC HMAC secret falls back to public default credential, enabling peer impersonation
No known exploitation. EPSS puts it in the 39th percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.5% chance of exploitation activity in the next 30 days, which ranks it in the 39th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
4 events over 1 day, from the signal feeds we watch.
- Record updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Scored 9.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Credential AccessT1552Unsecured Credentialshigh confidence
- Initial AccessT1078Valid Accountshigh confidence
Sources
References in the record
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