CVE-2020-12105

Name: CVE-2020-12105
Creator: NVD / NIST
Published: 2020-04-23T17:15:12.863+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 1.70%

Last modified Jun 17, 2026

CVE-2020-12105 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. OpenConnect through 8.08 mishandles negative return values from X509_check_ function calls, which might assist attackers in performing man-in-the-middle attacks.. EPSS estimates a 1.70% chance of exploitation in the next 30 days.

Description

OpenConnect through 8.08 mishandles negative return values from X509_check_ function calls, which might assist attackers in performing man-in-the-middle attacks.

Metrics

CVSS 3.1

5.9/10

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

EPSS Probability

1.70%

74.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-755

Affected Software

Vendor	Product	Versions
Infradead	Openconnect	<= 8.08
Opensuse	Leap	15.1

References

http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00039.htmlMailing List, Third Party Advisory
https://gitlab.com/openconnect/openconnect/-/merge_requests/96Third Party Advisory
https://security.gentoo.org/glsa/202006-15Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00039.htmlMailing List, Third Party Advisory
https://gitlab.com/openconnect/openconnect/-/merge_requests/96Third Party Advisory
https://security.gentoo.org/glsa/202006-15Third Party Advisory

Timeline

Published: Apr 23, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-12105?

OpenConnect through 8.08 mishandles negative return values from X509_check_ function calls, which might assist attackers in performing man-in-the-middle attacks.

How severe is CVE-2020-12105?

CVE-2020-12105 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 1.70% probability of exploitation in the next 30 days.

How do I fix CVE-2020-12105?

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-2020-12105?

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

Scan your code now

Source: NVD / NIST