Description

Privilege escalation due to invalid pointer in the Graphics component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-09-01T13:20:07.123Z",
  "pubdate": "2026-09-01T13:20:07.123Z",
  "executiveSummary": "A privilege escalation vulnerability exists within the Graphics component of Mozilla Firefox, originating from an invalid pointer dereference condition.\nThis vulnerability allows an attacker to achieve unauthorized privilege escalation by manipulating memory management within the graphics rendering pipeline.\nAffected products include Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2.\nThe risk is categorized as critical, as successful exploitation may allow a local or remote attacker to bypass sandbox security controls, execute arbitrary code with elevated privileges, or cause memory corruption that leads to system instability.\nExploitation generally requires an attacker to entice a user to process malicious content that triggers the flawed rendering path within the Graphics component.\nThe vulnerability highlights a significant failure in pointer validation, emphasizing the necessity for robust memory safety checks in components handling complex graphical data.",
  "technicalDetails": "The vulnerability resides within the Graphics rendering engine of Mozilla Firefox. The root cause is an invalid pointer state—likely a use-after-free or a null pointer dereference—that occurs when the engine processes specific graphical objects or rendering commands.\nWhen the Graphics component fails to properly validate the lifecycle of memory objects, an invalid pointer may persist in memory. If this pointer is accessed during subsequent rendering operations, it can lead to memory corruption.\nAttack flow typically involves the following steps: First, the attacker delivers a specially crafted payload, such as a malicious web page containing complex SVG, WebGL, or Canvas elements designed to trigger the specific state in the Graphics subsystem. Second, the browser's rendering process attempts to access an object whose reference has become invalid or improperly initialized.\nUpon accessing this invalid pointer, the attacker can hijack the instruction pointer or corrupt adjacent memory addresses. This memory corruption is often leveraged to bypass address space layout randomization (ASLR) and data execution prevention (DEP) mechanisms.\nThe privilege escalation occurs when the attacker transitions from the restricted sandbox environment to the privilege level of the browser process or, in some scenarios, the underlying operating system context. By overwriting function pointers or manipulating object metadata, the attacker can redirect control flow to shellcode or existing gadgets within the application's memory space.\nThis vulnerability is particularly concerning due to the complexity of the Graphics component, which handles high-speed data processing and complex memory allocation patterns. Without rigorous bounds checking and pointer validation before dereferencing, the Graphics pipeline becomes an attractive attack vector for escalating privileges.\nPost-exploitation impact includes full system compromise, exfiltration of sensitive user data, or the installation of persistent threats within the user session. Because this occurs at the component level, the sandbox integrity is compromised, effectively negating the isolation protections meant to protect the host machine from web-based malicious content."
}