# CVE-2020-12105: Security feature bypass in n/a

> Attackers can perform man-in-the-middle attacks due to mishandled negative return values in certificate checks, affecting OpenConnect users.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 23 Apr 2020
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2020-12105, GHSA-wr4v-x69c-q5jx, SUSE-SU-2020:1264-1, SUSE-SU-2020:1337-1, openSUSE-SU-2020:0694-1

## What is CVE-2020-12105?

CVE-2020-12105 is a medium-severity vulnerability in Opensuse Leap, published on 23 Apr 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### 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.

Weakness: CWE-755 (Improper Handling of Exceptional Conditions)

## Which versions are affected by CVE-2020-12105?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `openconnect` | SUSE:Linux Enterprise Workstation Extension 12 SP4 | All versions | 7.08-3.9.1 |
| `openconnect` | SUSE:Linux Enterprise Workstation Extension 12 SP5 | All versions | 7.08-3.9.1 |
| `openconnect` | SUSE:Linux Enterprise Workstation Extension 15 SP1 | All versions | 7.08-6.6.1 |
| `openconnect` | openSUSE:Leap 15.1 | All versions | 7.08-lp151.6.6.1 |

Products: Infradead Openconnect, Opensuse Leap.

## How do I fix CVE-2020-12105?

Upgrade to a fixed version.

## Is CVE-2020-12105 being exploited?

There is no known exploitation of CVE-2020-12105 in the wild and no public exploit code.

## Other vulnerabilities in Opensuse Leap

- [CVE-2013-7098](https://insights.sbomify.com/CVE-2013-7098/): Memory corruption in n/a (critical 9.8)
- [CVE-2012-3291](https://insights.sbomify.com/CVE-2012-3291/): Memory corruption in n/a (high 7.8)
- [CVE-2010-3901](https://insights.sbomify.com/CVE-2010-3901/): Security feature bypass in n/a (medium 6.4)
- [CVE-2012-6128](https://insights.sbomify.com/CVE-2012-6128/): Multiple stack-based buffer overflows in http.c in OpenConnect before 4.08 allow remote VPN gateways to cause a denial of service (applicati (medium 5.0)
- [CVE-2009-5009](https://insights.sbomify.com/CVE-2009-5009/): Use after free in n/a (medium 5.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-12105 and fix it if it is affected.

What it is: CVE-2020-12105 is a medium-severity vulnerability in Opensuse Leap, published on 23 Apr 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-12105 in the wild and no public exploit code.

Affected product: Opensuse Leap. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2020-12105/ (Markdown: https://insights.sbomify.com/CVE-2020-12105/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-12105
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-12105
- OSV: https://osv.dev/vulnerability/CVE-2020-12105

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-12105/
Summaries are generated and may contain mistakes; the official description above is the record.