Buffer Overflow Affecting openconnect package, versions <8.10-1


Severity

Recommended
low

Based on Debian security rating.

Threat Intelligence

EPSS
4.74% (92nd percentile)

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  • Snyk IDSNYK-DEBIAN14-OPENCONNECT-11762799
  • published10 Aug 2025
  • disclosed12 May 2020

Introduced: 12 May 2020

CVE-2020-12823  (opens in a new tab)
CWE-120  (opens in a new tab)

How to fix?

Upgrade Debian:14 openconnect to version 8.10-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream openconnect package and not the openconnect package as distributed by Debian. See How to fix? for Debian:14 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1