High Threat Security Alert (A26-07-37): Multiple Vulnerabilities in FireFox


 

Published on: 22 July 2026

Last update on: 24 July 2026

Description:

Mozilla has published the advisories (MFSA2026-68, MFSA2026-69 and MFSA2026-70) to address multiple vulnerabilities in Firefox. A remote attacker could entice a user to open a web page with specially crafted content on a vulnerable browser to exploit the vulnerabilities.

Reports indicated that proof-of-concept (PoC) exploit code for a denial-of-service vulnerability (CVE-2026-15718) and a security restriction bypass vulnerability (CVE-2026-15719) is publicly available and it is at high risk of exploitation. System administrators are advised to take immediate action to patch your affected systems or follow the recommendations provided by the product vendors to mitigate the elevated risk of cyber attacks.

 

Affected Systems:

  • Firefox ESR Windows versions prior to version 115.38, 140.13
  • Firefox Windows versions prior to version 153

 

Impact:

Successful exploitation of the vulnerabilities could lead to remote code execution, denial of service, elevation of privilege, information disclosure, security restriction bypass or spoofing on an affected system.

 

Recommendation:

Mozilla has released new versions of the product to address the issues and they can be downloaded at the following URLs:
Firefox 153 (Windows)
https://www.mozilla.org/en-US/download/all/?redirect_source=mozilla-org#product-desktop-release
Firefox ESR 115.38, 140.13 (Windows)
https://www.mozilla.org/en-US/download/all/?redirect_source=mozilla-org#product-desktop-esr

Users of affected systems should follow the recommendations provided by the vendor and take immediate actions to mitigate the risk.

 

More Information:

  • https://www.mozilla.org/en-US/security/advisories/mfsa2026-68/
  • https://www.mozilla.org/en-US/security/advisories/mfsa2026-69/
  • https://www.mozilla.org/en-US/security/advisories/mfsa2026-70/
  • https://www.hkcert.org/security-bulletin/mozilla-products-multiple-vulnerabilities_20260722
  • https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-15718 (to CVE-2026-15719)
  • https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-16349 (to CVE-2026-16412)


Tag: Firefox , Mozilla
Tags