Information disclosure due to uninitialized memory in the Graphics: Canvas2D component

Successful exploitation of CVE-2026-6749 could allow an attacker to read data from memory that has not been properly initialized. While the specific data exposed is not detailed, it could potentially include user data, browser settings, or even parts of the browser's internal state. This information could then be used for further attacks, such as identity theft or privilege escalation. The impact is heightened if the affected Firefox instance is running with elevated privileges or has access to sensitive resources. The Canvas2D component is widely used for rendering graphics and multimedia content, increasing the potential attack surface.

Users of Firefox versions 115.0.0 through 140.* are at risk, particularly those who frequently browse untrusted websites or interact with potentially malicious web content. Organizations deploying Firefox in enterprise environments should prioritize patching to mitigate this risk.

• firefox: Monitor Firefox's memory usage for unusual patterns using performance monitoring tools. Examine crash reports for indications of memory corruption related to the Canvas2D component. • generic web: Monitor web application logs for unusual requests targeting the Canvas2D API. Look for patterns that might indicate attempts to trigger memory errors.

1. 2026-04-21Disclosure

   disclosure

1. आरक्षित2026-04-21
2. प्रकाशित2026-04-21
3. संशोधित2026-04-22
4. EPSS अद्यतन2026-04-29

The primary mitigation for CVE-2026-6749 is to upgrade to Firefox version 150.0.0 or later. If immediate upgrading is not possible due to compatibility issues or testing requirements, consider implementing a Content Security Policy (CSP) to restrict the sources from which scripts can be loaded, potentially limiting the attacker's ability to exploit the vulnerability. Monitor Firefox's memory usage for unusual patterns that might indicate exploitation attempts. While a WAF is unlikely to directly mitigate this vulnerability, it can help detect and block malicious requests targeting the Canvas2D component.