# CVE-2020-12413: Information disclosure in Firefox

> Attackers can exploit timing side-channels in DHE ciphersuites to recover sensitive data, requiring users to disable DHE support.

- **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:** 16 Feb 2023
- **Updated:** 19 Mar 2025
- **Also known as:** DEBIAN-CVE-2020-12413, GHSA-4mgq-9qgw-ghcx

## What is CVE-2020-12413?

CVE-2020-12413 is a medium-severity vulnerability in Mozilla Firefox, published on 16 Feb 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Raccoon attack is a timing attack on DHE ciphersuites inherit in the TLS specification. To mitigate this vulnerability, Firefox disabled support for DHE ciphersuites.

Weakness: CWE-203 (Observable Discrepancy)

## Which versions are affected by CVE-2020-12413?

It affects 2 products.


Products: Mozilla Firefox, Mozilla Firefox Esr.

## How do I fix CVE-2020-12413?

Change a configuration setting.

## Is CVE-2020-12413 being exploited?

There is no known exploitation of CVE-2020-12413 in the wild and no public exploit code.

## Other vulnerabilities in Mozilla Firefox

- [CVE-2019-11708](https://insights.sbomify.com/CVE-2019-11708/): Mozilla Firefox and Thunderbird Sandbox Escape (critical 10.0, exploited in the wild)
- [CVE-2010-3765](https://insights.sbomify.com/CVE-2010-3765/): Mozilla Multiple Products Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2022-26486](https://insights.sbomify.com/CVE-2022-26486/): Mozilla Firefox Use-After-Free (critical 9.6, exploited in the wild)
- [CVE-2022-26485](https://insights.sbomify.com/CVE-2022-26485/): Mozilla Firefox Use-After-Free (high 8.8, exploited in the wild)
- [CVE-2019-11707](https://insights.sbomify.com/CVE-2019-11707/): Mozilla Firefox and Thunderbird Type Confusion (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-12413 and fix it if it is affected.

What it is: CVE-2020-12413 is a medium-severity vulnerability in Mozilla Firefox, published on 16 Feb 2023. 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-2020-12413 in the wild and no public exploit code.

Affected product: Mozilla Firefox. 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-2020-12413/ (Markdown: https://insights.sbomify.com/CVE-2020-12413/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-12413
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-12413
- OSV: https://osv.dev/vulnerability/CVE-2020-12413

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-12413/
Summaries are generated and may contain mistakes; the official description above is the record.