CVE-2020-12823

Name: CVE-2020-12823
Creator: NVD / NIST
Published: 2020-05-12T18:15:13.473+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 4.62%

Last modified Jun 17, 2026

CVE-2020-12823 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. OpenConnect 8.09 has a buffer overflow, causing a denial of service (application crash) or possibly unspecified other impact, via crafted certificate data to get_cert_name in gnutls.c.. EPSS estimates a 4.62% chance of exploitation in the next 30 days.

Description

OpenConnect 8.09 has a buffer overflow, causing a denial of service (application crash) or possibly unspecified other impact, via crafted certificate data to get_cert_name in gnutls.c.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

4.62%

90.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Infradead	Openconnect	8.09
Fedoraproject	Fedora	30
Fedoraproject	Fedora	31
Fedoraproject	Fedora	32
Debian	Debian Linux	8.0
Opensuse	Leap	15.1
Opensuse	Leap	15.2

References

http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00039.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00056.htmlMailing List, Third Party Advisory
https://bugs.gentoo.org/721570Exploit, Third Party Advisory
https://gitlab.com/openconnect/openconnect/-/merge_requests/108Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/05/msg00015.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/25MFX4AZE7RDCUWOL4ZOE73YBOPUMQDX/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AYSXLXAPXD2T73T6JMHI5G2WP7KHAGMN/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BEVTIH5UFX35CC7MVSYBGRM3D66ACFD5/
https://security.gentoo.org/glsa/202006-15Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00039.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00056.htmlMailing List, Third Party Advisory
https://bugs.gentoo.org/721570Exploit, Third Party Advisory
https://gitlab.com/openconnect/openconnect/-/merge_requests/108Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/05/msg00015.htmlMailing List, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/25MFX4AZE7RDCUWOL4ZOE73YBOPUMQDX/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AYSXLXAPXD2T73T6JMHI5G2WP7KHAGMN/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BEVTIH5UFX35CC7MVSYBGRM3D66ACFD5/
https://security.gentoo.org/glsa/202006-15Third Party Advisory

Timeline

Published: May 12, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-12823?

OpenConnect 8.09 has a buffer overflow, causing a denial of service (application crash) or possibly unspecified other impact, via crafted certificate data to get_cert_name in gnutls.c.

How severe is CVE-2020-12823?

CVE-2020-12823 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 4.62% probability of exploitation in the next 30 days.

How do I fix CVE-2020-12823?

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-2020-12823?

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

Scan your code now

Source: NVD / NIST