Klever-Go: Validator registration accepts an unvalidated BLS public key → consensus liveness DoS (CVE-2026-82407) | HOL Guard CVE

High · CVSS 7.0CVE-2026-82407

Klever-Go: Validator registration accepts an unvalidated BLS public key → consensus liveness DoS

Answer in brief

CVE-2026-82407 records a High severity (CVSS 7.0) vulnerability in Klever-Go: Validator registration accepts an unvalidated BLS public key → consensus liveness DoS. The current sources do not mark it as known exploited. The current feed maps klever-io/klever-go (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 23, 2026Updated Sep 23, 2026Source checked Sep 23, 2026First seen by HOL Sep 23, 2026Material review Sep 23, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.0
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 7.0. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps klever-io/klever-go (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
klever-io/klever-gogeneric	<1.7.20	1.7.20

Recommended response

Check inventory. Check lockfiles and deployed manifests for klever-io/klever-go.
Review the reported fix. Update klever-io/klever-go to 1.7.20 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 23, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 23, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 23, 2026

Sources and claim methodology

Upstream source description

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, core/kapp/validators/validators.go Register and the runtime validator update path accept a submitted BLSPublicKey without curve, prime-order subgroup, or nonzero validation. When a validator with a malformed key becomes eligible and is selected into a consensus group, MultiSigner.Reset and the corresponding signature verification creation path cannot deserialize the group key and cancel the slot. This causes repeated missed rounds and throughput degradation, and a network whose consensus group equals the eligible validator set can halt completely. Genesis validation is not affected because that path already performs CheckPublicKeyValid. This issue is fixed in version 1.7.20.

Quoted source text, attributed separately from HOL analysis.