MEDIUM
CVE-2020-12105
CWE-755Published: April 23, 2020· Updated: Jun 17, 2026
5.9
CVSS v3.1
Official 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.
Technical Analysis
CVE-2020-12105 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), with a CVSS base score of 5.9.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityHigh
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected Vendors & Products
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
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Official Patches & Advisories
All References (6)
→
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
Quick Facts
CVE IDCVE-2020-12105
CVSS Score5.9 / 10
SeverityMEDIUM
WeaknessCWE-755
CISA KEVNo
Affected2 vendor(s)
PublishedApr 23, 2020
Related CVEs (CWE-755)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2020-12105 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.