Full Report
Mozilla has released updates to address two critical flaws in Firefox for which it warned that exploit code has been published. The vulnerabilities are listed below - CVE-2026-15718, an invalid pointer in the JavaScript: WebAssembly component CVE-2026-15719, a site isolation in the DOM: Navigation component "We are aware that exploit code for this is public, however we are not aware of
Analysis Summary
# Vulnerability: Critical Exploitable Flaws in Mozilla Firefox
## CVE Details
- **CVE ID:** CVE-2026-15718 and CVE-2026-15719
- **CVSS Score:** Not explicitly listed (Categorized as Critical by Vendor)
- **CWE:** CWE-822 (Untrusted Pointer Dereference) for CVE-2026-15718; Site Isolation/Logic error for CVE-2026-15719.
## Affected Systems
- **Products:** Mozilla Firefox
- **Versions:** All versions prior to 152.0.6
- **Configurations:** Standard installations; specifically impacts JavaScript WebAssembly processing and DOM Navigation handling.
## Vulnerability Description
Mozilla has addressed two distinct critical security flaws:
1. **CVE-2026-15718:** An invalid pointer vulnerability within the JavaScript WebAssembly component. This likely allows for memory corruption when processing specially crafted WebAssembly code.
2. **CVE-2026-15719:** A site isolation flaw in the DOM: Navigation component. This vulnerability represents a breakdown in the browser's security boundary, potentially allowing cross-origin data access or bypassing navigation restrictions.
## Exploitation
- **Status:** PoC available (Exploit code is public); No known active exploitation in the wild as of the report date.
- **Complexity:** Medium
- **Attack Vector:** Network (Remote)
## Impact
- **Confidentiality:** High (Potential for cross-site data leakage)
- **Integrity:** High (Potential for arbitrary code execution via pointer manipulation)
- **Availability:** High (Potential for application crashes/DoS)
## Remediation
### Patches
- **Firefox 152.0.6:** Updates have been released to resolve both CVEs. Users are urged to update immediately.
### Workarounds
- No specific official workarounds are provided; institutional users should restrict access to untrusted websites until the patch is applied.
## Detection
- **Indicators of Compromise:** Browser crashes when interacting with specific WebAssembly modules or unusual cross-site navigation behavior.
- **Detection methods and tools:** Monitor for outdated browser versions (older than 152.0.6) using endpoint management software.
## References
- **Mozilla Foundation Security Advisory:** hxxps://www.mozilla[.]org/en-US/security/advisories/mfsa2026-67/
- **The Hacker News Article:** hxxps://thehackernews[.]com/2026/07/firefox-chrome-adobe-and-vmware-updates.html