CVE-2026-40094 | nimiq-blockchain: network-libp2p untrusted peer can crash address book via empty peer contact addresses

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.

Published: 2026-05-20 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-40094 is rated Low Risk (25/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.30%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-40094

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.03% 0.30% +0.27%
2 2026-05-21 — 0.03% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-40094

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 2.8 1.4 [email protected]

Weakness enumeration for CVE-2026-40094

Affected software / configurations for CVE-2026-40094

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-40094

cvelogic Threat Intelligence