CVE-2026-7320: Firefox Information Disclosure Vulnerability

CVE-2026-7320 Overview

CVE-2026-7320 is an information disclosure vulnerability affecting Mozilla Firefox's Audio/Video component. The vulnerability arises from incorrect boundary conditions (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer), which can allow an attacker to read sensitive memory contents that should not be accessible. This vulnerability is remotely exploitable over the network without requiring any user interaction or special privileges.

Critical Impact
Remote attackers can exploit incorrect boundary conditions in the Audio/Video component to access sensitive information from memory, potentially exposing confidential data processed by the browser.

Affected Products

Mozilla Firefox versions prior to 150.0.1
Mozilla Firefox ESR versions prior to 140.10.1
Mozilla Firefox ESR versions prior to 115.35.1

Discovery Timeline

April 28, 2026 - CVE-2026-7320 published to NVD
April 28, 2026 - Last updated in NVD database

Technical Details for CVE-2026-7320

Vulnerability Analysis

This vulnerability stems from improper handling of boundary conditions within Firefox's Audio/Video processing component. When the component processes certain media content, it fails to properly validate memory access boundaries, creating an opportunity for out-of-bounds memory reads. The flaw allows attackers to craft malicious media content that, when processed by the vulnerable component, triggers an information disclosure condition.

The vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), which encompasses various memory safety issues including buffer overflows and out-of-bounds access. In this case, the boundary condition error specifically enables unauthorized read access to memory regions outside the intended buffer.

Root Cause

The root cause lies in incorrect boundary condition validation within the Audio/Video component's memory handling routines. When processing media data, the component fails to properly verify that memory access operations remain within allocated buffer boundaries. This insufficient validation allows read operations to extend beyond intended memory regions, potentially exposing sensitive data stored in adjacent memory locations.

Attack Vector

The attack can be executed remotely over the network. An attacker could host malicious media content on a website or embed it in web pages. When a user visits the malicious page using a vulnerable Firefox version, the crafted Audio/Video content triggers the boundary condition error during processing, allowing the attacker to potentially extract sensitive information from the browser's memory space.

The vulnerability mechanism involves crafting media content that causes the Audio/Video component to perform memory read operations that exceed proper boundaries. Technical details about the specific exploitation technique can be found in Mozilla Bug Report #2027433 and the associated security advisories.

Detection Methods for CVE-2026-7320

Indicators of Compromise

Unusual memory access patterns or crashes within Firefox's Audio/Video processing components
Network traffic containing malformed or suspicious media content targeting Firefox browsers
Browser crash reports indicating faults in media processing routines

Detection Strategies

Monitor for Firefox browser versions older than 150.0.1, 140.10.1 (ESR), or 115.35.1 (ESR) in your environment
Implement network-based detection for potentially malicious media content targeting Firefox's Audio/Video component
Review browser crash telemetry for signs of memory access violations in media processing

Monitoring Recommendations

Deploy endpoint detection solutions to identify exploitation attempts targeting browser memory handling
Enable verbose logging for Firefox browser activity on sensitive systems
Monitor for network connections to known malicious domains serving exploit content

How to Mitigate CVE-2026-7320

Immediate Actions Required

Update Mozilla Firefox to version 150.0.1 or later immediately
Update Mozilla Firefox ESR to version 140.10.1 or 115.35.1 (depending on ESR channel) or later
Consider temporarily disabling automatic media playback until patches are applied
Restrict access to untrusted websites on systems where immediate patching is not possible

Patch Information

Mozilla has released security patches addressing this vulnerability in Firefox 150.0.1, Firefox ESR 140.10.1, and Firefox ESR 115.35.1. Detailed information about the fix is available in the following security advisories:

Organizations should prioritize updating all Firefox installations to the patched versions through their standard software update mechanisms.

Workarounds

Disable automatic media playback in Firefox settings (media.autoplay.default set to 5) until patching is complete
Use browser isolation or sandboxing technologies to limit potential impact
Implement content security policies to restrict media sources to trusted domains
Consider using alternative browsers temporarily on high-risk systems until updates can be applied

bash

# Firefox configuration example - disable autoplay
# Add to user.js or about:config
user_pref("media.autoplay.default", 5);
user_pref("media.autoplay.blocking_policy", 2);