# CVE-2022-37620: kangax html-minifier REDoS vulnerability

> Attackers can cause denial of service in applications using html-minifier by exploiting a Regular Expression Denial of Service flaw.

- **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:** Yes
- **Published:** 31 Oct 2022
- **Updated:** 1 Jun 2025
- **Also known as:** CLSA-2026-1774657356, CLSA-2026-1792745496, GHSA-pfq8-rq6v-vf5m, MINI-v7v7-j5qf-mwrq, ROOT-APP-NPM-CVE-2022-37620

## What is CVE-2022-37620?

CVE-2022-37620 is a high-severity denial of service vulnerability in n/a, published on 31 Oct 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A Regular Expression Denial of Service (ReDoS) flaw was found in kangax html-minifier 4.0.0 because of the reCustomIgnore regular expression.

Weakness: CWE-1333 (Inefficient Regular Expression Complexity)

## Which versions are affected by CVE-2022-37620?

2 open source packages ship an affected version, including html-minifier. It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `html-minifier` | npm | All versions to 4.0.0 | None |
| `html-minifier` | npm | All versions to 4.0.0 | None |

Products: Kangax Html-Minifier, Terser Html-Minifier-Terser.

## How do I fix CVE-2022-37620?

Upgrade to a fixed version.

## Is CVE-2022-37620 being exploited?

There is no known exploitation of CVE-2022-37620 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-37620 and fix it if it is affected.

What it is: CVE-2022-37620 is a high-severity denial of service vulnerability in n/a, published on 31 Oct 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-2022-37620 in the wild and no public exploit code.

Affected packages and fixed versions:
- html-minifier (npm): affected all versions up to 4.0.0; no fix listed
- html-minifier (npm): affected all versions up to 4.0.0; no fix listed

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-2022-37620/ (Markdown: https://insights.sbomify.com/CVE-2022-37620/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-37620
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-37620
- OSV: https://osv.dev/vulnerability/CVE-2022-37620

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-37620/
Summaries are generated and may contain mistakes; the official description above is the record.