How severe is CVE-2021-3580?

CVE-2021-3580 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-2021-3580 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3580?

CVE-2021-3580 primarily affects Redhat Enterprise Linux. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3580?

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-2021-3580 published?

CVE-2021-3580 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-3580

CVE-2021-3580 is a high-severity vulnerability in Redhat Enterprise Linux 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Redhat Enterprise Linux
Published: 2021-08-05
Last modified: 2026-06-17

Description

A flaw was found in the way nettle's RSA decryption functions handled specially crafted ciphertext. An attacker could use this flaw to provide a manipulated ciphertext leading to application crash and denial of service.

Frequently asked questions

What is CVE-2021-3580?: A flaw was found in the way nettle's RSA decryption functions handled specially crafted ciphertext. An attacker could use this flaw to provide a manipulated ciphertext leading to application crash and denial of service.
How severe is CVE-2021-3580?: CVE-2021-3580 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-2021-3580 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3580?: CVE-2021-3580 primarily affects Redhat Enterprise Linux. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3580?: 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-2021-3580 published?: CVE-2021-3580 was published on 2021-08-05 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:nettle_project:nettle:*:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*

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