CVE-2025-11710: Mozilla Firefox Information Disclosure Flaw

CVE-2025-11710 Overview

CVE-2025-11710 is a critical information disclosure vulnerability affecting Mozilla Firefox and Thunderbird browsers. A compromised web process can leverage malicious Inter-Process Communication (IPC) messages to cause the privileged browser process to reveal blocks of its memory to the compromised process. This memory disclosure vulnerability could expose sensitive information stored in the browser's privileged process memory, including credentials, session tokens, and other confidential data.

Critical Impact

A compromised web renderer process can exfiltrate sensitive memory contents from the privileged parent browser process through crafted IPC messages, potentially exposing credentials, cryptographic keys, and user data.

Affected Products

• Mozilla Firefox versions prior to 144
• Mozilla Firefox ESR versions prior to 115.29 and 140.4
• Mozilla Thunderbird versions prior to 144 and 140.4

Discovery Timeline

• October 14, 2025 - CVE-2025-11710 published to NVD
• November 3, 2025 - Last updated in NVD database

Technical Details for CVE-2025-11710

Vulnerability Analysis

This vulnerability (CWE-200: Exposure of Sensitive Information to an Unauthorized Actor) exists within Mozilla's IPC mechanism that facilitates communication between the sandboxed web content process and the privileged browser parent process. Mozilla employs a multi-process architecture where web content runs in isolated, sandboxed processes with limited privileges, while the parent browser process maintains elevated privileges to perform system-level operations.

The flaw allows a compromised content process to craft malicious IPC messages that trick the privileged parent process into disclosing portions of its memory space. This breaks the security boundary between the sandboxed content process and the privileged parent process, undermining the entire sandboxing model.

Root Cause

The root cause stems from improper validation of IPC message parameters in the privileged browser process. When processing certain IPC requests, the parent process fails to adequately verify bounds or memory regions specified in incoming messages. This allows an attacker who has already compromised a content process (through another vulnerability such as a JavaScript engine bug) to request arbitrary memory blocks from the parent process.

The vulnerability relates to how memory references are handled across process boundaries in Mozilla's IPC framework. Insufficient sanitization of memory range parameters enables the compromised process to specify memory regions that should not be accessible, resulting in the parent process copying and transmitting protected memory contents.

Attack Vector

Exploitation of CVE-2025-11710 requires an attacker to first compromise the web content process, typically through a separate vulnerability such as a use-after-free or type confusion bug in the JavaScript engine. Once the content process is compromised, the attacker can:

1. Craft malicious IPC messages with manipulated memory parameters
2. Send these messages to the privileged parent process
3. Receive memory blocks from the parent process that contain sensitive data
4. Parse the leaked memory for credentials, session cookies, encryption keys, or other valuable information

This attack chain represents a sandbox escape scenario where the attacker escalates from a compromised sandboxed process to obtaining sensitive data from the privileged process. For detailed technical information, refer to the Mozilla Bug Report.

Detection Methods for CVE-2025-11710

Indicators of Compromise

• Unusual IPC message patterns or volumes between content and parent processes
• Abnormal memory access patterns in the browser parent process
• Large data transfers from parent process to content process via IPC channels
• Crash reports indicating memory access violations in IPC handling code

Detection Strategies

• Monitor for suspicious browser process behavior including unexpected memory operations
• Implement endpoint detection rules for anomalous IPC communication patterns
• Deploy browser telemetry analysis to identify exploit chains targeting the content process
• Use SentinelOne's behavioral AI to detect post-exploitation memory enumeration activities

Monitoring Recommendations

• Enable enhanced logging for browser process communications where available
• Monitor network traffic for data exfiltration following browser exploitation
• Track browser crash reports that may indicate attempted exploitation
• Implement file integrity monitoring on browser binaries to detect tampering

How to Mitigate CVE-2025-11710

Immediate Actions Required

• Update Mozilla Firefox to version 144 or later immediately
• Update Mozilla Firefox ESR to version 115.29 or 140.4 or later
• Update Mozilla Thunderbird to version 144 or 140.4 or later
• Verify updates have been applied across all enterprise endpoints

Patch Information

Mozilla has released security patches addressing this vulnerability across multiple product lines. Organizations should reference the following security advisories for complete patch information:

• Mozilla Security Advisory MFSA-2025-81
• Mozilla Security Advisory MFSA-2025-82
• Mozilla Security Advisory MFSA-2025-83
• Mozilla Security Advisory MFSA-2025-84
• Mozilla Security Advisory MFSA-2025-85

Debian users should also apply updates as noted in Debian LTS Announcement #15 and Debian LTS Announcement #31.

Workarounds

• Implement network segmentation to limit potential data exfiltration paths
• Consider temporarily restricting access to untrusted web content on sensitive systems until patches can be applied
• Deploy browser isolation technologies to contain potential compromises
• Enable strict site isolation policies where supported to minimize cross-process attack surface