CVE-2026-40092: Nimiq nimiq-blockchain remote denial of service via DHT record panic

CVE-2026-40092 · Severity: high · CVSS 7.5 · Published 2026-05-20

A vulnerability in the Nimiq blockchain's key handling library allows a malicious user to crash any full node on the network. By sending a specially crafted record through the network's peer-to-peer discovery system, an attacker can cause the software to stop responding. This can lead to a complete service outage for affected nodes, disrupting the stability of the blockchain network.

Vendors: crates.io.

Quick answers

Is CVE-2026-40092 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-40092 being exploited in the wild.
How severe is CVE-2026-40092?
High severity, with a CVSS score of 7.5, published 20 May 2026.
Which products and versions are affected?
nimiq-keys (crates.io) <= 0.2.0, SEMVER:introduced=0,last_affected=0.2.0.
Is there a fix for CVE-2026-40092?
A patch was published on 2026-05-15: Patched in v1.4.0 of core-rs-albatross Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-40092 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-40092?
Check whether you run nimiq-keys (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A denial-of-service vulnerability exists in the `nimiq-keys` crate due to an unchecked return value when processing Ed25519 signatures. Specifically, the `TaggedPublicKey` implementation for `Ed25519PublicKey` calls `unwrap()` on the result of `Ed25519Signature::from_bytes(sig)`. If a malicious peer publishes a Kademlia DHT record containing a signature that is not exactly 64 bytes, the `try_from` call in the underlying `ed25519_zebra` library fails, causing the `unwrap()` to trigger a thread panic. This allows an unauthenticated remote attacker to crash any Nimiq full node that attempts to verify the crafted DHT record. The issue is fixed in version 1.4.0 of the core-rs-albatross repository.

Affected products

  • Nimiq nimiq-keys <= 0.2.0

Identifiers

  • CVE-2026-40092
  • GHSA-27w2-87xv-37c6

Timeline

  • 2026-05-15: disclosed
  • 2026-05-15: advisory
  • 2026-05-15: patched: Patched in v1.4.0 of core-rs-albatross

References

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