# CVE-2021-3959: Server-Side Request Forgery in Bitdefender GravityZone Update Server in Relay Mode (VA-10145)

> An attacker can proxy requests to the relay server via SSRF in Bitdefender GravityZone Update Server when relay mode is enabled.

- **Severity:** Medium 6.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/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:** No
- **Published:** 16 Dec 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-f622-26hm-xgj8

## What is CVE-2021-3959?

CVE-2021-3959 is a medium-severity server-side request forgery vulnerability in Bitdefender GravityZone, published on 16 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A Server-Side Request Forgery (SSRF) vulnerability in the EPPUpdateService component of Bitdefender Endpoint Security Tools allows an attacker to proxy requests to the relay server. This issue affects: Bitdefender Bitdefender GravityZone versions prior to 3.3.8.272

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2021-3959?

It affects 1 product.


Products: Bitdefender Gravityzone.

## How do I fix CVE-2021-3959?

No fix has been published for CVE-2021-3959 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-3959 being exploited?

There is no known exploitation of CVE-2021-3959 in the wild and no public exploit code.

## Other vulnerabilities in Bitdefender GravityZone

- [CVE-2017-8931](https://insights.sbomify.com/CVE-2017-8931/): Privilege escalation in n/a (critical 9.8)
- [CVE-2018-8955](https://insights.sbomify.com/CVE-2018-8955/): Code injection in n/a (critical 9.8)
- [CVE-2025-2244](https://insights.sbomify.com/CVE-2025-2244/): Insecure PHP deserialization issue in GravityZone Console (VA-12634) (critical 9.5)
- [CVE-2024-6980](https://insights.sbomify.com/CVE-2024-6980/): Verbose error handling issue in GravityZone Update Server proxy service (critical 9.2)
- [CVE-2022-2830](https://insights.sbomify.com/CVE-2022-2830/): Deserialization of Untrusted Data in GravityZone Console On-Premise (VA-10573) (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3959 and fix it if it is affected.

What it is: CVE-2021-3959 is a medium-severity server-side request forgery vulnerability in Bitdefender GravityZone, published on 16 Dec 2021. 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-2021-3959 in the wild and no public exploit code.

Affected product: Bitdefender GravityZone. 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-2021-3959/ (Markdown: https://insights.sbomify.com/CVE-2021-3959/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3959
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3959
- OSV: https://osv.dev/vulnerability/CVE-2021-3959

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3959/
Summaries are generated and may contain mistakes; the official description above is the record.