# CVE-2026-34069: Nimiq nimiq-consensus panic in RequestMacroChain handler

Source: https://junglewise.ai/threats/cve-2026-34069-nimiq-nimiq-consensus-panic-in-requestmacrochain-handler  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-14. Updated: 2026-05-11  
License: CC BY 4.0 with a link back

CVE-2026-34069 · Severity: medium · CVSS 5.3 · Published 2026-04-14

A vulnerability in the Nimiq blockchain consensus library allows an unauthenticated attacker to crash a node by sending a specially crafted network message. This results in a denial-of-service (DoS) condition, potentially disrupting the node's ability to participate in the blockchain network and process transactions. The issue affects the Albatross implementation of the Nimiq protocol.

Technologies: [Nimiq Proof-Of-Stake](https://junglewise.ai/threats/technologies/nimiq-proof-of-stake). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io), [Nimiq](https://junglewise.ai/threats/vendors/nimiq).

## Quick answers

**Is CVE-2026-34069 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-34069 being exploited in the wild.

**How severe is CVE-2026-34069?** Medium severity, with a CVSS score of 5.3, published 14 April 2026.

**Which products and versions are affected?** nimiq-consensus (crates.io) <= 1.2.2, SEMVER:introduced=0,last_affected=1.2.2; Nimiq Consensus <= 1.2.2.

**Is there a fix for CVE-2026-34069?** A patch was published on 2026-04-13: Fix released in version 1.3.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-34069 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-34069?** Check whether you run nimiq-consensus (crates.io), Nimiq Consensus or Nimiq Proof-Of-Stake 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 reachable assertion (CWE-617) exists in the `RequestMacroChain::handle` function of the `nimiq-consensus` crate. An unauthenticated P2P peer can send a `RequestMacroChain` message where the first locator hash on the victim's main chain corresponds to a micro block rather than a macro block. The handler fails to validate the block type before calling `get_macro_blocks()`, which subsequently triggers an `.unwrap()` on a `BlockchainError::BlockIsNotMacro` error, causing the task to panic. This vulnerability is fixed in version 1.3.0 of the Nimiq core-rs-albatross repository.

## Affected products

- Nimiq nimiq-consensus <= 1.2.2

## Identifiers

- CVE-2026-34069
- GHSA-48m6-486p-9j8p

## Timeline

- 2026-04-11: disclosed: Vulnerability reported to Nimiq
- 2026-04-13: advisory: GitHub Advisory GHSA-48m6-486p-9j8p published
- 2026-04-13: patched: Fix released in version 1.3.0

## References

- [https://api.github.com/users/jsdanielh](https://api.github.com/users/jsdanielh)
- [https://github.com/jsdanielh](https://github.com/jsdanielh)
- [https://api.github.com/users/jsdanielh/gists%7B/gist_id%7D](https://api.github.com/users/jsdanielh/gists%7B/gist_id%7D)
- [https://api.github.com/users/jsdanielh/repos](https://api.github.com/users/jsdanielh/repos)
- [https://avatars.githubusercontent.com/u/2374448?v=4](https://avatars.githubusercontent.com/u/2374448?v=4)
- [https://api.github.com/users/jsdanielh/events%7B/privacy%7D](https://api.github.com/users/jsdanielh/events%7B/privacy%7D)

## Related threats

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- [nimiq-primitives: Node crash due to missing interlink validation in election macro block proposals](https://junglewise.ai/threats/cve-2026-34065-nimiq-primitives-node-crash-due-to-missing-interlink-validation)
- [nimiq-account: Vesting insufficient funds error can panic](https://junglewise.ai/threats/cve-2026-34064-nimiq-account-vesting-insufficient-funds-error-can-panic)