CVE-2026-10702 in Firefox
Summary
by MITRE • 06/03/2026
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 151.0.3.
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Analysis
by VulDB Data Team • 06/04/2026
The vulnerability described represents a just-in-time compilation issue within the JavaScript engine component of the affected software, specifically impacting the JIT execution path that translates JavaScript code into optimized machine instructions. This type of flaw falls under the broader category of compiler and interpreter vulnerabilities that can lead to unpredictable behavior and potential security exploits. The issue manifests in the JIT compiler's ability to generate incorrect machine code during runtime optimization, creating a scenario where malicious JavaScript code could trigger unintended execution paths or memory corruption patterns.
The technical nature of this vulnerability involves the JIT compiler's improper handling of certain JavaScript constructs or optimization decisions that result in malformed machine code generation. Such miscompilation can occur when the compiler makes incorrect assumptions about data types, memory layout, or execution flow during the optimization phase. The flaw typically arises from insufficient validation or incorrect handling of edge cases during the compilation process, where the compiler's optimization algorithms fail to account for all possible runtime conditions. This miscompilation can lead to memory corruption, control flow hijacking, or arbitrary code execution when the optimized code is executed.
The operational impact of this vulnerability extends beyond simple performance degradation to potentially enable remote code execution attacks. When exploited, the JIT miscompilation can allow attackers to bypass security mitigations such as address space layout randomization, stack canaries, or control flow integrity protections. The vulnerability's exploitation potential is particularly concerning given that JavaScript engines are integral to web browsers and other applications that process untrusted content. Attackers could craft malicious web pages or JavaScript code that triggers the specific code path leading to miscompilation, potentially resulting in full system compromise. The fact that this vulnerability was patched in Firefox 151.0.3 demonstrates the severity of the issue, as it required immediate remediation to prevent exploitation in the wild.
Security professionals should note that this vulnerability aligns with common weakness enumerations such as CWE-682, which covers incorrect calculation or computation, and potentially CWE-129, which addresses insufficient validation of array indices. The attack surface is particularly relevant to the ATT&CK framework's technique T1059.007 for JavaScript and T1059.001 for command and scripting interpreter, as exploitation would involve crafting malicious JavaScript payloads that leverage the JIT miscompilation. Organizations should prioritize updating to the patched version and implement additional security measures such as sandboxing, content security policies, and regular security assessments to protect against similar JIT-related vulnerabilities. The vulnerability serves as a reminder of the critical importance of thorough testing and validation of compiler optimizations, particularly in security-sensitive environments where JIT compilers process untrusted input.