How severe is CVE-2021-45720?

CVE-2021-45720 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-45720 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45720?

CVE-2021-45720 affects Lru Project Lru. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-45720?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-45720 published?

CVE-2021-45720 was published on 2021-12-26 and last updated on 2026-06-17.

CVE-2021-45720

CVE-2021-45720 is a high-severity vulnerability in Lru Project Lru with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Lru Project Lru
Published: 2021-12-26
Last modified: 2026-06-17

Description

An issue was discovered in the lru crate before 0.7.1 for Rust. The iterators have a use-after-free, as demonstrated by an access after a pop operation.

Frequently asked questions

What is CVE-2021-45720?: An issue was discovered in the lru crate before 0.7.1 for Rust. The iterators have a use-after-free, as demonstrated by an access after a pop operation.
How severe is CVE-2021-45720?: CVE-2021-45720 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-45720 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45720?: CVE-2021-45720 affects Lru Project Lru. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-45720?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-45720 published?: CVE-2021-45720 was published on 2021-12-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:lru_project:lru:*:*:*:*:*:rust:*:*

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