What is CVE-2020-12105?

CVE-2020-12105 is a medium-severity vulnerability in Infradead Openconnect, classified under Improper Handling of Exceptional Conditions. CVSS score: 5.9/10. Published 2020-04-23.

How severe is CVE-2020-12105?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Infradead Openconnect

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.

Published 2020-04-23 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.017 (76.8th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 77th percentile — 76.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: +0.000

Affected products

Infradead Openconnect
openSUSE Leap — versions 15.1

Weakness classification (CWE)

CWE-755 — Improper Handling of Exceptional Conditions

References

gitlab.com/openconnect/openconnect/-/merge_requests/96 (Third Party Advisory)
lists.opensuse.org/opensuse-security-announce/2020-05/msg00039.html (vendor-advisory, Mailing List, Third Party Advisory)
security.gentoo.org/glsa/202006-15 (vendor-advisory, Third Party Advisory)

Frequently asked questions

What is CVE-2020-12105?: CVE-2020-12105 is a medium-severity vulnerability in Infradead Openconnect, classified under Improper Handling of Exceptional Conditions. CVSS score: 5.9/10. Published 2020-04-23.
How severe is CVE-2020-12105?: Medium severity. CVSS v3 base score is 5.9 out of 10.