CVE-2026-34069
MEDIUMCVE-2026-34069 is a medium-severity (CVSS 5.3) Reachable Assertion vulnerability in nimiq-consensus. O3 Security confirms whether CVE-2026-34069 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
nimiq-consensus panics via RequestMacroChain micro-block locator
Blast Radius
nimiq-consensusReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
nimiq/core-rs-albatross is a Rust implementation of the Nimiq Proof-of-Stake protocol based on the Albatross consensus algorithm. In versions 1.2.2 and below, an unauthenticated p2p peer can cause the RequestMacroChain message handler task to panic. Sending a RequestMacroChain message where the first locator hash on the victim’s main chain is a micro block hash (not a macro block hash) causes said panic. The RequestMacroChain::handle 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). This issue has been fixed in version 1.3.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | nimiq-consensus | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nimiq-consensus. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of nimiq-consensus has shipped for CVE-2026-34069 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-34069 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-34069. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-34069 in your dependencies?
O3 detects CVE-2026-34069 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.