CVE-2026-40094: nimiq-blockchain provides persistent block storage for Nimiq's Rust implementation. In versions 1.3.0 and prior, network-libp2p discovery accepts sign...

Description

nimiq-blockchain provides persistent block storage for Nimiq's Rust implementation. In versions 1.3.0 and prior, network-libp2p discovery accepts signed PeerContact updates from untrusted peers and stores them in a peer contact book, eventually leading to address book crash. A PeerContact can legally contain an empty addresses list (no intrinsic validation enforces non-empty). Later, PeerContactBook::known_peers builds an address book by taking addresses.first().expect("every peer should have at least one address"). If the attacker has inserted a signed peer contact with addresses=[], any call to get_address_book (RPC/web client) can panic and crash the node/RPC task depending on panic settings. This issue has been fixed in version 1.4.0.

Metrics

CVSS 3.1

4.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

EPSS Probability

0.30%

21.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-754

References

Timeline

Published: May 20, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-40094?

nimiq-blockchain provides persistent block storage for Nimiq's Rust implementation. In versions 1.3.0 and prior, network-libp2p discovery accepts signed PeerContact updates from untrusted peers and stores them in a peer contact book, eventually leading to address book crash. A PeerContact can legally contain an empty addresses list (no intrinsic validation enforces non-empty). Later, PeerContactBook::known_peers builds an address book by taking addresses.first().expect("every peer should have at least one address"). If the attacker has inserted a signed peer contact with addresses=[], any call to get_address_book (RPC/web client) can panic and crash the node/RPC task depending on panic settings. This issue has been fixed in version 1.4.0.

How severe is CVE-2026-40094?

CVE-2026-40094 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 0.30% probability of exploitation in the next 30 days.

How do I fix CVE-2026-40094?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.