CVE-2026-92076 in Firefox
Summary
by MITRE • 09/15/2026
Incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 156 and Firefox ESR 153.3.
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Analysis
by VulDB Data Team • 09/15/2026
The identified security issue resides within the networking subsystem of Mozilla Firefox, specifically involving incorrect boundary condition handling during data processing operations. In software engineering, boundary conditions refer to edge cases where input values are at the extreme ends of a range or set of acceptable inputs. When these boundaries are not correctly validated or managed by the application logic, it can lead to unexpected behavior that attackers may exploit. This particular flaw suggests that under specific circumstances involving network requests or responses, the browser failed to properly check limits such as buffer sizes, array indices, or memory allocation thresholds before performing operations on incoming data streams.
From a technical perspective, this type of vulnerability is commonly classified under CWE-190 Integer Overflow or Wraparound if it involves arithmetic errors leading to insufficient bounds checking, or potentially CWE-20 Improper Input Validation if the issue stems from failing to sanitize or verify external network inputs before processing them within the networking stack. The core technical flaw likely allows for an out-of-bounds memory access when parsing certain HTTP headers, cookies, or payload data sent over a connection. If exploited successfully, this could result in arbitrary code execution with the privileges of the user running the browser, as modern browsers often run network handling components in contexts that may have elevated permissions relative to standard web content sandboxing layers depending on the specific architecture implementation at the time.
The operational impact of such a vulnerability is significant because it affects one of the most widely used internet applications globally. An attacker could craft a malicious website or manipulate network traffic to trigger this boundary condition error during normal browsing activities, such as loading a webpage with specially crafted headers or interacting with web services that return malformed responses. Successful exploitation might allow for remote code execution, leading to data theft, installation of malware, or complete compromise of the user's system integrity. Given its location in the networking component, it represents a high-risk vector since network interactions are frequent and often involve untrusted third-party content from various domains across the internet.
Mozilla addressed this vulnerability by releasing updates for Firefox version 156 and Firefox Extended Support Release (ESR) version 153.3. These patches likely involved rigorous code reviews, static analysis enhancements, and dynamic testing to identify where boundary checks were missing or incorrectly implemented within the networking module. The fix ensures that all input data processed by the network stack is strictly validated against defined limits before any memory operations are performed. This aligns with secure coding practices recommended by industry standards such as OWASP which emphasize robust input validation and error handling to prevent exploitation of logical flaws in application components.
To mitigate risks associated with similar vulnerabilities, users should ensure their browsers are updated to the latest stable versions promptly after release. Organizations relying on Firefox ESR for enterprise environments must verify that patch management processes include timely deployment of these security updates. Additionally, developers working on network-facing applications can adopt defensive programming techniques such as using safe string handling libraries, implementing strict type checking, and conducting regular code audits focused on boundary condition logic to prevent recurrence of such issues in future software releases.