CVE-2026-45039
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedRustFS 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe internode RPC layer in RustFS uses HMAC-SHA256 authentication with a shared secret. The get_shared_secret() function in crates/ecstore/src/rpc/http_auth.rs falls back to a hardcoded default secret key 'rustfsadmin' when neither RUSTFS_RPC_SECRET nor the global S3 secret key is configured. This allows unauthenticated attackers to authenticate to the RPC layer using the known default key.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify RustFS installationCheck for RustFS binary, service, or process on the system (e.g., ps aux | grep rustfs, which rustfs, or check installed packages)Affected if RustFS is installed and running as a service
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Verify RUSTFS_RPC_SECRET environment variableInspect environment variables for the running RustFS process (e.g., cat /proc/<pid>/environ | tr '\0' '\n' | grep RUSTFS_RPC_SECRET) or check shell environment (echo $RUSTFS_RPC_SECRET)Affected if RUSTFS_RPC_SECRET is not set or is empty
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Inspect RustFS configuration filesReview RustFS configuration files (typically in /etc/rustfs/, ~/.config/rustfs/, or the application's config directory) for rpc_secret, secret_key, or authentication settingsAffected if No explicit RPC secret is configured in any config file
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Check for hardcoded default secret in useExamine logs, configuration, or code for references to 'rustfsadmin' as the default credential, or attempt to correlate authentication behavior with the default secretAffected if The default secret 'rustfsadmin' is being used for RPC authentication
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Confirm internode RPC exposureCheck network listeners or firewall rules to determine if the RustFS RPC port (typically 3000-4000 range or as configured) is exposed to untrusted networksAffected if Internode RPC layer is accessible from untrusted network segments
You are affected if RustFS is running with internode RPC enabled and the RUSTFS_RPC_SECRET environment variable is unset or empty, causing fallback to the default hardcoded secret 'rustfsadmin'.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedConfigure the RUSTFS_RPC_SECRET environment variable or ensure the global S3 secret key is properly set on all nodes before deployment, and upgrade to version 1.0.0-beta.2 or later.
1.0.0-beta.2
- Upgrade RustFS to version 1.0.0-beta.2 or later
- After upgrading, configure either the RUSTFS_RPC_SECRET environment variable or the global S3 secret key to ensure the hard-coded default is not used
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45039 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-45039 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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