# CVE-2023-25166: Regular Expression Denial of Service (ReDoS) Vulnerability


- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 8 Feb 2023
- **Updated:** 10 Mar 2025
- **Also known as:** GHSA-c2jc-4fpr-4vhg

## What is CVE-2023-25166?

CVE-2023-25166 is a medium-severity vulnerability in hapijs formula, published on 8 Feb 2023. 

### Official description

formula is a math and string formula parser. In versions prior to 3.0.1 crafted user-provided strings to formula's parser might lead to polynomial execution time and a denial of service. Users should upgrade to 3.0.1+. There are no known workarounds for this vulnerability.

Weakness: CWE-1333 (Inefficient Regular Expression Complexity)

## Which versions are affected by CVE-2023-25166?

2 open source packages ship an affected version, including @sideway/formula. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@sideway/formula` | npm | All versions | 3.0.1 |
| `@sideway/formula` | npm | All versions | 3.0.1 |

Products: Hapi Formula.

## How do I fix CVE-2023-25166?

Upgrade @sideway/formula to 3.0.1 or later.

## Is CVE-2023-25166 being exploited?

There is no known exploitation of CVE-2023-25166 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-25166 and fix it if it is affected.

What it is: CVE-2023-25166 is a medium-severity vulnerability in hapijs formula, published on 8 Feb 2023. 
Exploitation: There is no known exploitation of CVE-2023-25166 in the wild and no public exploit code.

Affected packages and fixed versions:
- @sideway/formula (npm): affected all versions; fixed in 3.0.1
- @sideway/formula (npm): affected all versions; fixed in 3.0.1

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-2023-25166/ (Markdown: https://insights.sbomify.com/CVE-2023-25166/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-25166
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-25166
- OSV: https://osv.dev/vulnerability/CVE-2023-25166

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-25166/
Summaries are generated and may contain mistakes; the official description above is the record.