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nimiq-keys: Unchecked Ed25519 signature length in TaggedPublicKey::verify causes remote node panic via DHT

High severity GitHub Reviewed Published May 15, 2026 in nimiq/core-rs-albatross

Package

cargo nimiq-keys (Rust)

Affected versions

<= 0.2.0

Patched versions

None

Description

Impact

A malicious network peer can crash any Nimiq full node by publishing a crafted Kademlia DHT record containing a TaggedSigned<ValidatorRecord, KeyPair> with a signature field whose byte length is not exactly 64. When the victim node's DHT verifier calls TaggedSigned::verify, execution reaches Ed25519Signature::from_bytes(sig).unwrap() in the TaggedPublicKey implementation for Ed25519PublicKey. The from_bytes call fails because ed25519_zebra::Signature::try_from rejects slices not 64 bytes, and the unwrap() panics. The BLS TaggedPublicKey implementation correctly returns false on error; only the Ed25519 implementation panics.

Patches

The patch for this vulnerability is formally released as part of v1.4.0.

Workarounds

No known workarounds.

Resources

See PR.

References

@jsdanielh jsdanielh published to nimiq/core-rs-albatross May 15, 2026
Published to the GitHub Advisory Database May 15, 2026
Reviewed May 15, 2026

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS score

Weaknesses

Unchecked Return Value

The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. Learn more on MITRE.

CVE ID

CVE-2026-40092

GHSA ID

GHSA-27w2-87xv-37c6

Credits

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