How severe is CVE-2021-45700?

No CVSS score has been assigned to CVE-2021-45700 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2021-45700?

CVE-2021-45700 affects the following packages: ckb (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2021-45700?

Update ckb to 0.40.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45700 is resolved across your whole dependency graph.

How do I detect CVE-2021-45700 in my crates.io dependencies?

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

How do I mitigate CVE-2021-45700 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 CVE-2021-45700 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-45700 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 CVE-2021-45700?

CVE-2021-45700 has an EPSS (Exploit Prediction Scoring System) score of 1.1%, placing it in the 64th 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.

When was CVE-2021-45700 published, and has it been updated?

CVE-2021-45700 was published on August 25, 2021 and was last updated on November 8, 2023. 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

CVE-2021-45700 — ckb

CVE-2021-45700 is a security vulnerability in ckb. A fix is available for ckb — see the affected versions and patch details below.

Process crashes when the cell used as DepGroup is not alive

Also known asGHSA-cw98-cx2m-9qqgRUSTSEC-2021-0109

Published

Aug 25, 2021

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

1.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs64th percentile — riskier than 64% of all scored CVEsHighest risk

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

Real-World Exposure

1 pkg affected

🦀ckb

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

An issue was discovered in the ckb crate before 0.40.0 for Rust. Attackers can cause a denial of service (Nervos CKB blockchain node crash) via a dead call that is used as a DepGroup.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`ckb`	all versions	0.40.0`cargo update -p ckb --precise 0.40.0`

Affected Products

1 product · 1 configurations

Application

ckbnervos

< 0.40.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ckb, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ckb to 0.40.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45700 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 It's easy to create a malign transaction which uses the dead cell as the DepGroup in the DepCells. The transaction can crash all the receiving nodes.

O3 Security · Impact-Aware SCA

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