How severe is CVE-2021-45680?

No CVSS score has been assigned to CVE-2021-45680 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2021-45680?

CVE-2021-45680 affects the following packages: vec-const (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2021-45680?

Update vec-const to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45680 is resolved across your whole dependency graph.

How do I detect CVE-2021-45680 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vec-const. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2021-45680 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.

How does O3 Security protect against CVE-2021-45680?

O3 pinpoints whether CVE-2021-45680 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2021-45680 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-45680 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-2021-45680?

CVE-2021-45680 has an EPSS (Exploit Prediction Scoring System) score of 1.1%, placing it in the 62th 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.

What type of vulnerability is CVE-2021-45680?

CVE-2021-45680 is classified as Out-of-bounds Write (CWE-787). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-45680 published, and has it been updated?

CVE-2021-45680 was published on June 17, 2022 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-2021-45680

CVE-2021-45680 is a Out-of-bounds Write vulnerability in vec-const. O3 Security confirms whether CVE-2021-45680 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

vec-const attempts to construct a Vec from a pointer to a const slice

Also known asGHSA-x76r-966h-5qv9RUSTSEC-2021-0082

Published

Jun 17, 2022

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Aug 19, 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 CVEs62th percentile — riskier than 62% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

🦀vec-const

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

Affected versions of this crate claimed to construct a const Vec with nonzero length and capacity, but that cannot be done because such a Vec requires a pointer from an allocator.

The implementation was later changed to just construct a std::borrow::Cow.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`vec-const`	all versions	2.0.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vec-const. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update vec-const to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-45680 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.
How O3 protects you
O3 pinpoints whether CVE-2021-45680 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2021-45680. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Affected versions of this crate claimed to construct a const `Vec` with nonzero length and capacity, but that cannot be done because such a `Vec` requires a pointer from an allocator. The implementation was later changed to just construct a `std::borrow::Cow`.

O3 Security · Impact-Aware SCA

Is CVE-2021-45680 in your dependencies?

O3 detects CVE-2021-45680 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works