# CVE-2020-1968: Raccoon attack

> Attackers can eavesdrop on encrypted TLS communications by exploiting DH secret reuse in OpenSSL, requiring DH ciphersuites.

- **Severity:** Low 3.7 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/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:** 9 Sep 2020
- **Updated:** 16 Apr 2026
- **Also known as:** DEBIAN-CVE-2020-1968, DLA-2378-1, GHSA-mh8f-5gw2-5wgh, SUSE-SU-2020:14491-1, SUSE-SU-2020:14511-1, UBUNTU-CVE-2020-1968

## What is CVE-2020-1968?

CVE-2020-1968 is a low-severity vulnerability in Canonical Ubuntu Linux, published on 9 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Raccoon attack exploits a flaw in the TLS specification which can lead to an attacker being able to compute the pre-master secret in connections which have used a Diffie-Hellman (DH) based ciphersuite. In such a case this would result in the attacker being able to eavesdrop on all encrypted communications sent over that TLS connection. The attack can only be exploited if an implementation re-uses a DH secret across multiple TLS connections. Note that this issue only impacts DH ciphersuites and not ECDH ciphersuites. This issue affects OpenSSL 1.0.2 which is out of support and no longer receiving public updates. OpenSSL 1.1.1 is not vulnerable to this issue. Fixed in OpenSSL 1.0.2w (Affected 1.0.2-1.0.2v).

Weakness: CWE-203 (Observable Discrepancy)

## Which versions are affected by CVE-2020-1968?

It affects 15 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `openssl` | SUSE:Linux Enterprise Point of Sale 11 SP3 | All versions | 0.9.8j-0.106.34.1 |
| `openssl` | SUSE:Linux Enterprise Server 11 SP4-LTSS | All versions | 0.9.8j-0.106.34.1 |
| `openssl1` | SUSE:Linux Enterprise Server 11-SECURITY | All versions | 1.0.1g-0.58.27.2 |

Products: Canonical Ubuntu Linux, Debian Debian Linux, Fujitsu M10-1 Firmware, Fujitsu M10-4 Firmware, Fujitsu M10-4s Firmware, Fujitsu M12-1 Firmware, Fujitsu M12-2 Firmware, Fujitsu M12-2s Firmware, Openssl Openssl, Oracle Ethernet Switch Es1-24 Firmware, Oracle Ethernet Switch Es2-64 Firmware, Oracle Ethernet Switch Es2-72 Firmware, Oracle Ethernet Switch Tor-72 Firmware, Oracle Jd Edwards World Security, Oracle Peoplesoft Enterprise Peopletools.

## How do I fix CVE-2020-1968?

Upgrade to a fixed version.

## Is CVE-2020-1968 being exploited?

There is no known exploitation of CVE-2020-1968 in the wild and no public exploit code.

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-1968 and fix it if it is affected.

What it is: CVE-2020-1968 is a low-severity vulnerability in Canonical Ubuntu Linux, published on 9 Sep 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-2020-1968 in the wild and no public exploit code.

Affected product: Canonical Ubuntu Linux. 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-2020-1968/ (Markdown: https://insights.sbomify.com/CVE-2020-1968/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-1968
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-1968
- OSV: https://osv.dev/vulnerability/CVE-2020-1968

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-1968/
Summaries are generated and may contain mistakes; the official description above is the record.