# CVE-2025-8262: yarnpkg Yarn hosted-git-resolver.js explodeHostedGitFragment redos

> Remote attackers can cause denial of service in Yarn via inefficient regular expression complexity in the hosted-git-resolver component.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Jul 2025
- **Updated:** 28 Jul 2025
- **Also known as:** BELL-CVE-2025-8262, DEBIAN-CVE-2025-8262, GHSA-9xhp-f235-5v37, MINI-r5rp-6854-5vpj, UBUNTU-CVE-2025-8262

## What is CVE-2025-8262?

CVE-2025-8262 is a medium-severity denial of service vulnerability in yarnpkg Yarn, published on 28 Jul 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was found in yarnpkg Yarn up to 1.22.22. It has been classified as problematic. Affected is the function explodeHostedGitFragment of the file src/resolvers/exotics/hosted-git-resolver.js. The manipulation leads to inefficient regular expression complexity. It is possible to launch the attack remotely. The patch is identified as 97731871e674bf93bcbf29e9d3258da8685f3076. It is recommended to apply a patch to fix this issue.

Weakness: CWE-400 (Uncontrolled Resource Consumption), CWE-1333 (Inefficient Regular Expression Complexity)

## Which versions are affected by CVE-2025-8262?

It affects 1 product.


Products: Yarnpkg Yarn.

## How do I fix CVE-2025-8262?

Apply the vendor's patch.

## Is CVE-2025-8262 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-8262 exists.

## Other vulnerabilities in yarnpkg Yarn

- [CVE-2019-5448](https://insights.sbomify.com/CVE-2019-5448/): Missing Encryption of Sensitive Data in yarn (high 8.1)
- [CVE-2019-10773](https://insights.sbomify.com/CVE-2019-10773/): Yarn Improper link resolution before file access (Link Following) (high 7.8)
- [CVE-2021-4435](https://insights.sbomify.com/CVE-2021-4435/): Yarn: untrusted search path (high 7.7)
- [CVE-2020-8131](https://insights.sbomify.com/CVE-2020-8131/): Path Traversal in Yarn (high 7.5)
- [CVE-2019-15608](https://insights.sbomify.com/CVE-2019-15608/): TOCTOU Race Condition in Yarn (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-8262 and fix it if it is affected.

What it is: CVE-2025-8262 is a medium-severity denial of service vulnerability in yarnpkg Yarn, published on 28 Jul 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-8262 exists.

Affected product: yarnpkg Yarn. 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-2025-8262/ (Markdown: https://insights.sbomify.com/CVE-2025-8262/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-8262
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-8262
- OSV: https://osv.dev/vulnerability/CVE-2025-8262

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-8262/
Summaries are generated and may contain mistakes; the official description above is the record.