How severe is CVE-2026-46545?

CVE-2026-46545 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-46545?

CVE-2026-46545 affects the following packages: nimiq-primitives (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2026-46545?

Update nimiq-primitives to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46545 is resolved across your whole dependency graph.

How do I detect CVE-2026-46545 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nimiq-primitives, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-46545 if there is no patch (or I can't update yet)?

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.

Is CVE-2026-46545 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-46545 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-46545?

CVE-2026-46545 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 47th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-46545?

CVE-2026-46545 is classified as CWE-248 (CWE-248). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-46545 published, and has it been updated?

CVE-2026-46545 was published on June 9, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🦀

🦀 crates.io

Not in CISA KEV

HIGH severity

CVE-2026-46545 — nimiq-primitives

HIGHFix: nimiq/core-rs-albatross#3762

CVE-2026-46545 is a high-severity (CVSS 7.5) CWE-248 vulnerability in nimiq-primitives. A fix is available for nimiq-primitives — see the affected versions and patch details below.

nimiq-primitives: Panic DoS in trie chunk processing via ROOT-keyed item

Also known asGHSA-mw3q-r9wh-h2ff

Published

Jun 9, 2026

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 26, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

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-2026-46545.

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs47th percentile — riskier than 47% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2026-46545 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 380,066 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🦀nimiq-primitives

Real-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

Impact

A remote, unauthenticated denial-of-service vulnerability in MerkleRadixTrie::put_chunk allows any state-sync peer to crash any node performing state synchronization (freshly joining nodes and recovering nodes).

A malicious peer can respond to a RequestChunk with a ResponseChunk::Chunk whose first TrieItem.key is the empty (ROOT) key. The chunk passes sorting, range, and Merkle-proof validation, but when put_raw tries to store a value at the root node, it calls TrieNode::put_value(...).unwrap(), which returns Err(RootCantHaveValue) and panics, aborting the node process. The panic fires on the first malicious chunk the victim commits; no rate limit or authentication gate caps the attack.

Impacted: any node running state sync against untrusted peers — this includes fresh nodes performing initial download and existing nodes recovering from data loss. Honest nodes never construct ROOT-keyed items, so non-syncing operation is unaffected.

Patches

See PR.

Workarounds

There is no safe in-process workaround: any peer serving state-sync data can trigger the crash and the code path is not guarded by a feature flag.

Resources

Fix commit: (link to the merged PR commit, once merged)
Affected code: primitives/trie/src/trie.rs — put_chunk (around line 819) and put_raw (around line 351)

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`nimiq-primitives`	all versions	1.5.0`cargo update -p nimiq-primitives --precise 1.5.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nimiq-primitives, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update nimiq-primitives to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46545 is resolved across your whole dependency graph.
Workarounds
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.

Frequently Asked Questions

### Impact A remote, unauthenticated denial-of-service vulnerability in `MerkleRadixTrie::put_chunk` allows any state-sync peer to crash any node performing state synchronization (freshly joining nodes and recovering nodes). A malicious peer can respond to a `RequestChunk` with a `ResponseChunk::Chunk` whose first `TrieItem.key` is the empty (ROOT) key. The chunk passes sorting, range, and Merkle-proof validation, but when `put_raw` tries to store a value at the root node, it calls `TrieNode::put_value(...).unwrap()`, which returns `Err(RootCantHaveValue)` and panics, aborting the node proce