How severe is CVE-2021-26951?

CVE-2021-26951 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26951 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26951?

CVE-2021-26951 affects Calamine Project Calamine. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26951?

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

When was CVE-2021-26951 published?

CVE-2021-26951 was published on 2021-02-09 and last updated on 2026-06-17.

CVE-2021-26951

CVE-2021-26951 is a critical-severity vulnerability in Calamine Project Calamine with a CVSS 3.x base score of 9.8. 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Calamine Project Calamine
Published: 2021-02-09
Last modified: 2026-06-17

Description

An issue was discovered in the calamine crate before 0.17.0 for Rust. It allows attackers to overwrite heap-memory locations because Vec::set_len is used without proper memory claiming, and this uninitialized memory is used for a user-provided Read operation, as demonstrated by Sectors::get.

Frequently asked questions

What is CVE-2021-26951?: An issue was discovered in the calamine crate before 0.17.0 for Rust. It allows attackers to overwrite heap-memory locations because Vec::set_len is used without proper memory claiming, and this uninitialized memory is used for a user-provided Read operation, as demonstrated by Sectors::get.
How severe is CVE-2021-26951?: CVE-2021-26951 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26951 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26951?: CVE-2021-26951 affects Calamine Project Calamine. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26951?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-26951 published?: CVE-2021-26951 was published on 2021-02-09 and last updated on 2026-06-17.

References

https://rustsec.org/advisories/RUSTSEC-2021-0015.html

Affected products (1)

cpe:2.3:a:calamine_project:calamine:*:*:*:*:*:rust:*:*

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