# CVE-2021-25640: Open Redirect or SSRF vulnerability usage of parseURL

> Attackers can bypass host whitelisting in Apache Dubbo to perform Server-Side Request Forgery or open redirects via the parseURL method.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 31 May 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-gw4j-4229-q4px

## What is CVE-2021-25640?

CVE-2021-25640 is a medium-severity server-side request forgery vulnerability in Apache Dubbo, published on 31 May 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

In Apache Dubbo prior to 2.6.9 and 2.7.9, the usage of parseURL method will lead to the bypass of white host check which can cause open redirect or SSRF vulnerability.

Weakness: CWE-601 (URL Redirection to Untrusted Site), CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2021-25640?

4 open source packages ship an affected version, including org.apache.dubbo:dubbo and com.alibaba:dubbo. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.dubbo:dubbo` | Maven | From 2.5.0 | 2.7.10 |
| `org.apache.dubbo:dubbo` | Maven | From 2.5.0 | 2.7.10 |
| `com.alibaba:dubbo` | Maven | From 2.5.0 | 2.6.9 |
| `com.alibaba:dubbo` | Maven | From 2.5.0 | 2.6.9 |

Products: Apache Dubbo.

## How do I fix CVE-2021-25640?

Upgrade org.apache.dubbo:dubbo to 2.7.10 or later.

## Is CVE-2021-25640 being exploited?

There is no known exploitation of CVE-2021-25640 in the wild and no public exploit code.

## Other vulnerabilities in Apache Dubbo

- [CVE-2023-29234](https://insights.sbomify.com/CVE-2023-29234/): Bypass serialize checks in Apache Dubbo (critical 9.8)
- [CVE-2023-46279](https://insights.sbomify.com/CVE-2023-46279/): Apache Dubbo: Bypass deny serialize list check in Apache Dubbo (critical 9.8)
- [CVE-2021-32824](https://insights.sbomify.com/CVE-2021-32824/): Regular expression Denial of Service in MooTools (critical 9.8)
- [CVE-2022-39198](https://insights.sbomify.com/CVE-2022-39198/): Apache Dubbo Hession Deserialization Vulnerability Gadgets Bypass (critical 9.8)
- [CVE-2021-43297](https://insights.sbomify.com/CVE-2021-43297/): Dubbo Hessian cause RCE when parse error (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-25640 and fix it if it is affected.

What it is: CVE-2021-25640 is a medium-severity server-side request forgery vulnerability in Apache Dubbo, published on 31 May 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-25640 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.dubbo:dubbo (Maven): affected from 2.5.0; fixed in 2.7.10
- org.apache.dubbo:dubbo (Maven): affected from 2.5.0; fixed in 2.7.10
- com.alibaba:dubbo (Maven): affected from 2.5.0; fixed in 2.6.9
- com.alibaba:dubbo (Maven): affected from 2.5.0; fixed in 2.6.9

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-2021-25640/ (Markdown: https://insights.sbomify.com/CVE-2021-25640/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-25640
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-25640
- OSV: https://osv.dev/vulnerability/CVE-2021-25640

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-25640/
Summaries are generated and may contain mistakes; the official description above is the record.