CVE-2026-74948 in Firefox
Summary
by MITRE • 08/18/2026
Information disclosure in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, and Firefox ESR 153.1.
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Analysis
by VulDB Data Team • 08/18/2026
The identified security flaw resides within the graphics subsystem of Mozilla Firefox, representing a critical category of information disclosure vulnerabilities where sensitive data is inadvertently exposed to unauthorized entities or processes. This specific issue stems from improper handling of graphical resources during rendering operations, potentially allowing an attacker with local access or through crafted web content to extract memory contents that were not intended for public consumption. Such flaws often arise when the browser fails to properly isolate graphics buffers or clears sensitive information before reusing them for subsequent rendering tasks, leading to potential leakage of cryptographic keys, session tokens, or other confidential data stored in video memory or system RAM associated with the graphical pipeline.
From a technical perspective, this vulnerability aligns closely with CWE-200, which categorizes exposure of sensitive information to an unauthorized actor, and potentially CWE-134 for use of externally-controlled format strings if string formatting within graphics drivers is involved. The attack vector likely involves manipulating specific rendering contexts or triggering edge cases in the GPU driver interaction layer where memory cleanup routines are bypassed or executed incorrectly. By exploiting this flaw, a maliciously crafted webpage could potentially read residual data from previous graphical operations, such as previously rendered images containing user credentials or private documents displayed within tabs that have since been closed but whose graphics buffers remain allocated and uncleared in the system's virtual address space.
The operational impact of this vulnerability is significant because it undermines the fundamental security model of web browsers regarding memory isolation and data confidentiality. If successfully exploited, an attacker could gain access to sensitive user information without needing direct file system access or complex privilege escalation techniques. This compromises user privacy and can lead to account takeover if session cookies or authentication tokens are leaked. Furthermore, such disclosures can facilitate further attacks by providing attackers with the context needed to craft more precise exploits against other components of the browser stack or connected services. The risk is particularly acute for users who handle sensitive data online, as even partial information leakage can be aggregated to reconstruct full credentials or personal identifiable information.
Mitigation strategies primarily rely on applying the vendor-provided patches that address these memory management and isolation flaws within the graphics component. Users must ensure they are running Firefox version 154, Firefox Extended Support Release (ESR) version 115.39, ESR version 140.14, or ESR version 153.1, as these releases contain the necessary code corrections to properly clear graphics buffers and enforce stricter memory access controls. In addition to updating software, organizations should implement strict content security policies and disable unnecessary browser features that interact with low-level hardware acceleration if possible, reducing the attack surface. Regular monitoring of vulnerability databases and prompt application of security updates remain essential practices for maintaining a secure browsing environment against such information disclosure threats.