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

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official 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.

[ Fixes ]Fixes and patches

• github.com/klever-io/klever-go 1.7.20Fixed version · GitHub Advisories · go package github.com/klever-io/klever-go: upgrade to 1.7.20 or later (affected <= 1.7.19)

[ Packages ]Affected open-source packages

• github.com/klever-io/klever-go goAffected <= 1.7.19 · fixed in 1.7.20 · GHSA-9wh6-9hq7-9688

[ References ]References

• github.com/klever-io/klever-go/commit/11606a90ccc289f93d0175994733229b332d9cff
• github.com/klever-io/klever-go/commit/642da967893884d635986fed3c43bdc679cbfe8f
• github.com/klever-io/klever-go/releases/tag/v1.7.20
• github.com/klever-io/klever-go/security/advisories/GHSA-9wh6-9hq7-9688