What’s Vulnerable › Vulnerabilities

CVE-2021-45699

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-12-27 · updated 2026-06-17
• Weakness: CWE-770

Description

An issue was discovered in the ckb crate before 0.40.0 for Rust. Remote attackers may be able to conduct a 51% attack against the Nervos CKB blockchain by triggering an inability to allocate memory for the misbehavior HashMap.

Affected products

• Nervos Ckb: before 0.40.0 — fixed in 0.40.0

How to fix

Upgrade to a fixed version: Nervos Ckb 0.40.0. Check the vendor advisory for mitigations.

References

• https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/ckb/RUSTSEC-2021-0108.md
• https://rustsec.org/advisories/RUSTSEC-2021-0108.html
• https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/ckb/RUSTSEC-2021-0108.md
• https://rustsec.org/advisories/RUSTSEC-2021-0108.html

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