# CVE-2021-46900: Weak cryptography in n/a

> Sympa uses a predictable cookie as a password salt and XSS protection, allowing attackers to bypass security mechanisms and potentially access sensitive data.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/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:** 31 Dec 2023
- **Updated:** 17 Apr 2025
- **Also known as:** DEBIAN-CVE-2021-46900, GHSA-qvwx-3j2c-25v2, UBUNTU-CVE-2021-46900

## What is CVE-2021-46900?

CVE-2021-46900 is a high-severity vulnerability in n/a, published on 31 Dec 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Sympa before 6.2.62 relies on a cookie parameter for certain security objectives, but does not ensure that this parameter exists and has an unpredictable value. Specifically, the cookie parameter is both a salt for stored passwords and an XSS protection mechanism.

Weakness: CWE-327 (Use of a Broken or Risky Cryptographic Algorithm)

## Which versions are affected by CVE-2021-46900?

It affects 1 product.


Products: Sympa Sympa.

## How do I fix CVE-2021-46900?

Upgrade to a fixed version.

## Is CVE-2021-46900 being exploited?

There is no known exploitation of CVE-2021-46900 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2012-2352](https://insights.sbomify.com/CVE-2012-2352/): Missing authorization in n/a (high 7.5)
- [CVE-2008-4476](https://insights.sbomify.com/CVE-2008-4476/): Path traversal in n/a (medium 6.9)
- [CVE-2015-1306](https://insights.sbomify.com/CVE-2015-1306/): Information disclosure in n/a (medium 5.0)
- [CVE-2008-1648](https://insights.sbomify.com/CVE-2008-1648/): Denial of service in n/a (medium 5.0)
- [CVE-2004-1735](https://insights.sbomify.com/CVE-2004-1735/): Cross-site scripting in n/a (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-46900 and fix it if it is affected.

What it is: CVE-2021-46900 is a high-severity vulnerability in n/a, published on 31 Dec 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-2021-46900 in the wild and no public exploit code.

Affected product: n/a. 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-2021-46900/ (Markdown: https://insights.sbomify.com/CVE-2021-46900/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-46900
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-46900
- OSV: https://osv.dev/vulnerability/CVE-2021-46900

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-46900/
Summaries are generated and may contain mistakes; the official description above is the record.