# CVE-2025-45525: Null dereference in microlight

> A null pointer dereference in the microlight library can cause an application crash when processing specific CSS values, though exploitation is disputed.

- **Severity:** Low 2.9 (`CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Jun 2025
- **Updated:** 26 Aug 2025

## What is CVE-2025-45525?

CVE-2025-45525 is a low-severity vulnerability in asvd microlight, published on 17 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A NULL pointer dereference vulnerability has been identified in the JavaScript library microlight version 0.0.7, a lightweight syntax highlighting library. When processing elements with non-standard CSS color values, the library fails to validate the result of a regular expression match before accessing its properties, leading to an uncaught TypeError and potential application crash. NOTE: this is disputed by multiple parties because there is no common scenario in which an adversary can insert those non-standard values.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-45525?


## How do I fix CVE-2025-45525?

No fix has been published for CVE-2025-45525 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-45525 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-45525 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-45525 and fix it if it is affected.

What it is: CVE-2025-45525 is a low-severity vulnerability in asvd microlight, published on 17 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-45525 exists.

Affected product: asvd microlight. 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-2025-45525/ (Markdown: https://insights.sbomify.com/CVE-2025-45525/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-45525
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-45525
- OSV: https://osv.dev/vulnerability/CVE-2025-45525

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-45525/
Summaries are generated and may contain mistakes; the official description above is the record.