Full Report
Multiple vulnerabilities have been discovered in Mozilla Firefox, the most severe of which could allow for arbitrary code execution. Mozilla Firefox is a web browser used to access the Internet. Successful exploitation of the most severe of these vulnerabilities could allow for arbitrary code execution. Depending on the privileges associated with the user an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.
Analysis Summary
# Vulnerability: Mozilla Firefox Memory Corruption and Integer Overflow Leading to RCE
## CVE Details
- CVE ID: CVE-2025-49709, CVE-2025-49710
- CVSS Score: Not explicitly provided, but severity suggests **High**
- CWE: Memory Corruption (likely), Integer Overflow
## Affected Systems
- Products: Mozilla Firefox
- Versions: Versions prior to 139.0.4
- Configurations: Any installation of the affected Firefox versions. Impact is higher for users with administrative privileges.
## Vulnerability Description
Multiple vulnerabilities exist in Mozilla Firefox. The two detailed flaws are:
1. **CVE-2025-49709**: Certain canvas operations could lead to memory corruption.
2. **CVE-2025-49710**: An integer overflow was present in the `OrderedHashTable` used by the JavaScript engine.
Successful exploitation of the most severe vulnerability could result in **Arbitrary Code Execution (ACE)**. An attacker could subsequently install programs, view/change/delete data, or create new user accounts, depending on the privileges of the exploited user account.
## Exploitation
- Status: Not exploited in the wild (as of advisory date)
- Complexity: Likely Low to Medium (due to ACE via browser attack vector)
- Attack Vector: Network (via malicious websites/content) via Drive-by Compromise ([T1189])
## Impact
- Confidentiality: High (Potential to access user data)
- Integrity: High (Potential to modify/delete data or install programs)
- Availability: Medium to High (Depending on capabilities installed by the attacker)
## Remediation
### Patches
- Apply updates provided by Mozilla to systems running Firefox versions prior to 139.0.4. (Specifically referencing **MFSA2025-47**)
### Workarounds
- Restrict use of certain websites.
- Block downloads/attachments.
- Block JavaScript within the browser.
- Restrict browser extensions.
## Detection
- Indicators of compromise: Unexplained process creation or elevated privileges following web browsing activity.
- Detection methods and tools: Enable and monitor anti-exploitation features (DEP, WDEG, SIP, Gatekeeper). Implement M1050: Exploit Protection.
## References
- Vendor Advisories:
- https://www.mozilla.org/en-US/security/advisories/
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-47/
- References to CVEs:
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-49709
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-49710