HIGH · 7.5

CVE-2026-34063

Nimiq's network-libp2p is a Nimiq network implementation based on libp2p. Prior to version 1.3.0, `network-libp2p` discovery uses a libp2p `ConnectionHandler` state machine. the handler assumes there ...

Vulnerability Description

Nimiq's network-libp2p is a Nimiq network implementation based on libp2p. Prior to version 1.3.0, `network-libp2p` discovery uses a libp2p `ConnectionHandler` state machine. the handler assumes there is at most one inbound and one outbound discovery substream per connection. if a remote peer opens/negotiate the discovery protocol substream a second time on the same connection, the handler hits a `panic!(\"Inbound already connected\")` / `panic!(\"Outbound already connected\")` path instead of failing closed. This causes a remote crash of the networking task (swarm), taking the node's p2p networking offline until restart. The patch for this vulnerability is formally released as part of v1.3.0. No known workarounds are available.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
NimiqNimiq Proof-Of-Stake< 1.3.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-34063?

CVE-2026-34063 is a vulnerability with a CVSS score of 7.5 (HIGH). Nimiq's network-libp2p is a Nimiq network implementation based on libp2p. Prior to version 1.3.0, `network-libp2p` discovery uses a libp2p `ConnectionHandler` state machine. the handler assumes there ...

How severe is CVE-2026-34063?

CVE-2026-34063 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-34063?

Check the references section above for vendor advisories and patch information. Affected products include: Nimiq Nimiq Proof-Of-Stake.