How severe is GHSA-h9cc-w26m-j342?

GHSA-h9cc-w26m-j342 has a CVSS score of 4.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-h9cc-w26m-j342?

GHSA-h9cc-w26m-j342 affects the following packages: nimiq-keys (crates.io). Ecosystems affected: crates.io.

How do I fix GHSA-h9cc-w26m-j342?

Update nimiq-keys to 1.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h9cc-w26m-j342 is resolved across your whole dependency graph.

How do I detect GHSA-h9cc-w26m-j342 in my crates.io dependencies?

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

How do I mitigate GHSA-h9cc-w26m-j342 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 GHSA-h9cc-w26m-j342 actively exploited in the wild?

No public exploit code has been indexed for GHSA-h9cc-w26m-j342 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 GHSA-h9cc-w26m-j342?

GHSA-h9cc-w26m-j342 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 32th 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 GHSA-h9cc-w26m-j342?

GHSA-h9cc-w26m-j342 is classified as Reachable Assertion (CWE-617). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-h9cc-w26m-j342 published, and has it been updated?

GHSA-h9cc-w26m-j342 was published on May 21, 2026 and was last updated on June 10, 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

MEDIUM severity

GHSA-h9cc-w26m-j342 — nimiq-keys

MEDIUMFix: nimiq/core-rs-albatross#3713

GHSA-h9cc-w26m-j342 is a medium-severity (CVSS 4.3) Reachable Assertion vulnerability in nimiq-keys. A fix is available for nimiq-keys — see the affected versions and patch details below.

nimiq-keys: Denial of service in Ed25519 multisig delinearization via invalid curve points

Also known asCVE-2026-46542

Published

May 21, 2026

Updated

Jun 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 1, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

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 GHSA-h9cc-w26m-j342.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk+0.17%

Lower risk than most CVEs32th percentile — riskier than 32% of all scored CVEsHighest risk

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

How urgent is this, really

GHSA-h9cc-w26m-j342 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 381,682 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-keys

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 denial-of-service vulnerability exists in the Ed25519 multisig delinearization code path. Ed25519PublicKey::delinearize() in keys/src/multisig/mod.rs called .unwrap() on curve point decompression, which panics when a public key is constructed from 32 bytes that do not represent a valid point on the Ed25519 curve. Ed25519PublicKey construction only validates byte length, not curve membership, so invalid keys can reach the delinearization path and crash the hosting process.

A secondary panic existed in Commitment::From<[u8; 32]>, which similarly called .unwrap() on a failing curve point decompression.

Who is affected: Browser and desktop wallet users of the web-client WASM library and the nimiq-wallet crate, when initiating a multisig operation with an attacker-supplied public key. An attacker must convince the user to include a crafted public key in a multisig setup — this is not a remotely triggerable node/validator crash.

Who is NOT affected: Validator nodes, consensus, blockchain, mempool, and networking code. There is no on-chain multisig account type; multisig is a purely client-side construct, and no validator/consensus code calls the multisig delinearization path.

Patches

See PR.

Workarounds

No code-level workaround exists short of the patch. Users of wallet applications can mitigate exposure by only performing multisig operations with public keys received from trusted sources.

Resources

Affected code: keys/src/multisig/mod.rs, keys/src/multisig/commitment.rs

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`nimiq-keys`	all versions	1.4.0`cargo update -p nimiq-keys --precise 1.4.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nimiq-keys, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update nimiq-keys to 1.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h9cc-w26m-j342 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 denial-of-service vulnerability exists in the Ed25519 multisig delinearization code path. `Ed25519PublicKey::delinearize()` in `keys/src/multisig/mod.rs` called `.unwrap()` on curve point decompression, which panics when a public key is constructed from 32 bytes that do not represent a valid point on the Ed25519 curve. `Ed25519PublicKey` construction only validates byte length, not curve membership, so invalid keys can reach the delinearization path and crash the hosting process. A secondary panic existed in `Commitment::From<[u8; 32]>`, which similarly called `.unwrap()` on a f