CVE-2021-20213

Name: CVE-2021-20213
Creator: NVD / NIST
Published: 2021-03-25T19:15:12.97+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.57%

Last modified Jun 17, 2026

CVE-2021-20213 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A flaw was found in Privoxy in versions before 3.0.29. Dereference of a NULL-pointer that could result in a crash if accept-intercepted-requests was enabled, Privoxy failed to get the request destination from the Host header and a memory allocation failed.. EPSS estimates a 1.57% chance of exploitation in the next 30 days.

Description

A flaw was found in Privoxy in versions before 3.0.29. Dereference of a NULL-pointer that could result in a crash if accept-intercepted-requests was enabled, Privoxy failed to get the request destination from the Host header and a memory allocation failed.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.57%

72.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-476

Affected Software

Vendor	Product	Versions
Privoxy	Privoxy	< 3.0.29

References

https://bugzilla.redhat.com/show_bug.cgi?id=1928739Issue Tracking, Patch, Third Party Advisory
https://security.gentoo.org/glsa/202107-16Third Party Advisory
https://www.privoxy.org/3.0.29/user-manual/whatsnew.htmlRelease Notes, Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1928739Issue Tracking, Patch, Third Party Advisory
https://security.gentoo.org/glsa/202107-16Third Party Advisory
https://www.privoxy.org/3.0.29/user-manual/whatsnew.htmlRelease Notes, Vendor Advisory

Timeline

Published: Mar 25, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20213?

How severe is CVE-2021-20213?

CVE-2021-20213 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.57% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20213?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20213?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST