# CVE-2022-28229: Denial of service in userver

> Attackers can cause denial of service in userver via crafted HTTP requests exploiting hash collisions.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 23 Dec 2022
- **Updated:** 15 Apr 2025
- **Also known as:** GHSA-8mr2-8r3v-fj69

## What is CVE-2022-28229?

CVE-2022-28229 is a high-severity denial of service vulnerability in userver, published on 23 Dec 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The hash functionality in userver before 42059b6319661583b3080cab9b595d4f8ac48128 allows attackers to cause a denial of service via crafted HTTP request, involving collisions.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2022-28229?

It affects 1 product.


Products: Userver Userver.

## How do I fix CVE-2022-28229?

No fix has been published for CVE-2022-28229 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-28229 being exploited?

There is no known exploitation of CVE-2022-28229 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-28229 and fix it if it is affected.

What it is: CVE-2022-28229 is a high-severity denial of service vulnerability in userver, published on 23 Dec 2022. 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-2022-28229 in the wild and no public exploit code.

Affected product: userver. 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-2022-28229/ (Markdown: https://insights.sbomify.com/CVE-2022-28229/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-28229
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-28229
- OSV: https://osv.dev/vulnerability/CVE-2022-28229

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-28229/
Summaries are generated and may contain mistakes; the official description above is the record.