How severe is CVE-2021-32920?

CVE-2021-32920 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-2021-32920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32920?

CVE-2021-32920 primarily affects Prosody. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-32920?

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-2021-32920 published?

CVE-2021-32920 was published on 2021-05-13 and last updated on 2026-06-17.

CVE-2021-32920

CVE-2021-32920 is a high-severity vulnerability in Prosody 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Prosody
Published: 2021-05-13
Last modified: 2026-06-17

Description

Prosody before 0.11.9 allows Uncontrolled CPU Consumption via a flood of SSL/TLS renegotiation requests.

Frequently asked questions

What is CVE-2021-32920?: Prosody before 0.11.9 allows Uncontrolled CPU Consumption via a flood of SSL/TLS renegotiation requests.
How severe is CVE-2021-32920?: CVE-2021-32920 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-2021-32920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32920?: CVE-2021-32920 primarily affects Prosody. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-32920?: 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-2021-32920 published?: CVE-2021-32920 was published on 2021-05-13 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:prosody:prosody:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

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