# CVE-2018-25049: email-existence index.js redos

> An attacker can cause a denial of service in the email-existence library by triggering inefficient regular expression complexity.

- **Severity:** Low 3.0 (`CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 27 Dec 2022
- **Updated:** 11 Apr 2025
- **Also known as:** GHSA-p27h-4cpf-fw48

## What is CVE-2018-25049?

CVE-2018-25049 is a low-severity denial of service vulnerability in email-existence, published on 27 Dec 2022. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

A vulnerability was found in email-existence. It has been rated as problematic. Affected by this issue is some unknown functionality of the file index.js. The manipulation leads to inefficient regular expression complexity. The name of the patch is 0029ba71b6ad0d8ec0baa2ecc6256d038bdd9b56. It is recommended to apply a patch to fix this issue. VDB-216854 is the identifier assigned to this vulnerability.

Weakness: CWE-1333 (Inefficient Regular Expression Complexity)

## Which versions are affected by CVE-2018-25049?

2 open source packages ship an affected version, including email-existence. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `email-existence` | npm | All versions to 0.1.6 | None |
| `email-existence` | npm | All versions to 0.1.6 | None |

Products: Email-Existence Project Email-Existence.

## How do I fix CVE-2018-25049?

No fix has been published for CVE-2018-25049 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-25049 being exploited?

There is no known exploitation of CVE-2018-25049 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-25049 and fix it if it is affected.

What it is: CVE-2018-25049 is a low-severity denial of service vulnerability in email-existence, published on 27 Dec 2022. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2018-25049 in the wild and no public exploit code.

Affected packages and fixed versions:
- email-existence (npm): affected all versions up to 0.1.6; no fix listed
- email-existence (npm): affected all versions up to 0.1.6; 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-2018-25049/ (Markdown: https://insights.sbomify.com/CVE-2018-25049/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-25049
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-25049
- OSV: https://osv.dev/vulnerability/CVE-2018-25049

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-25049/
Summaries are generated and may contain mistakes; the official description above is the record.