CVE-2026-34069 is a medium-severity (CVSS 5.3) Reachable Assertion vulnerability in nimiq-consensus. No vendor fix is recorded yet; mitigation options are listed below.
nimiq-consensus panics via RequestMacroChain micro-block locator
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-34069.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-34069 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-34069 can be triaged on real exposure rather than presence alone.
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 Security finds CVE-2026-34069 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.