nimiq-consensus panics via RequestMacroChain micro-block locator

CVE-2026-34069 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

Impact

An unauthenticated p2p peer can cause the RequestMacroChain message handler task to panic by sending a RequestMacroChain message where the first locator hash that is on the victim’s main chain is a micro block hash (not a macro block hash).

In RequestMacroChain::handle, the handler selects the locator based only on "is on main chain", then calls get_macro_blocks() and panics via .unwrap() when the selected hash is not a macro block (BlockchainError::BlockIsNotMacro).

Patches

The patch for this vulnerability](https://github.com/nimiq/core-rs-albatross/pull/3660) is formally released as part of v1.3.0.

Workarounds

No known workarounds.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2026-04-13 16:36:00 UTC
Updated
2026-04-15 20:56:43 UTC
GitHub reviewed
2026-04-13 16:36:00 UTC
NVD published
2026-04-13

EPSS Score

Score Percentile
0.04% 11.63%

CVSS Scores

Base score Version Severity Vector
5.3 3.1 —
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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.

Identifiers

Type Value
GHSA GHSA-48m6-486p-9j8p ↗
CVE CVE-2026-34069 ↗

CWEs

CWE id Name
CWE-617 Reachable Assertion

Credits

  • jsdanielh (analyst)
  • 1seal (finder)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
rust nimiq-consensus <= 1.2.2 — —

References

cvelogic Threat Intelligence