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0xCERT Security Advisory 0xCERT-2026-0175
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Advisory-ID:  0xCERT-2026-0175
Severity:     High
Published:    2026-09-23T20:17:16.707Z
Updated:      2026-10-08T22:46:36.952Z
Chains:       n/a
URL:          https://www.0xcert.com/advisory/0xCERT-2026-0175

Title: CVE-2026-82407: Klever-Go

Summary
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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 el…

Details
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Summary
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.

Severity
High (CVSS 7), as scored by NVD.

Weakness
- - CWE-20

Recommended actions
- - Check whether you run or depend on the affected component and version
- - Apply the vendor's fix or mitigation from the references below

Source & attribution
This 0xCERT advisory summarises CVE-2026-82407 from the U.S. National Vulnerability Database: https://nvd.nist.gov/vuln/detail/CVE-2026-82407. Details may change; refer to the original source for the authoritative record.

References
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- - https://nvd.nist.gov/vuln/detail/CVE-2026-82407
- - https://github.com/klever-io/klever-go/commit/11606a90ccc289f93d0175994733229b332d9cff
- - https://github.com/klever-io/klever-go/commit/642da967893884d635986fed3c43bdc679cbfe8f
- - https://github.com/klever-io/klever-go/releases/tag/v1.7.20
- - https://github.com/klever-io/klever-go/security/advisories/GHSA-9wh6-9hq7-9688
- - https://github.com/klever-io/klever-go/security/advisories/GHSA-9wh6-9hq7-9688

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