CVE-2023-5172 in Firefox
Summary
by MITRE • 10/25/2023
A hashtable in the Ion Engine could have been mutated while there was a live interior reference, leading to a potential use-after-free and exploitable crash. This vulnerability affects Firefox < 118.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 10/25/2023
The vulnerability identified as CVE-2023-5172 represents a critical memory safety issue within Firefox's Ion Engine, which is the Just-In-Time compiler responsible for optimizing JavaScript execution. This flaw manifests as a hashtable mutation during active reference scenarios, creating a dangerous condition where memory locations can be accessed after they have been freed. The vulnerability specifically impacts Firefox versions prior to 118, making it a significant concern for users running older browser versions. The Ion Engine's hashtable implementation fails to properly manage reference counts during concurrent operations, allowing for a race condition that can be exploited by malicious actors.
The technical nature of this vulnerability aligns with CWE-415, which describes improper handling of double free conditions and memory management errors. When the hashtable undergoes mutation while interior references remain active, the memory management system cannot accurately track object lifetimes. This creates a use-after-free condition where pointers to freed memory locations may still be accessible, potentially allowing attackers to execute arbitrary code or cause application crashes. The flaw occurs at the intersection of concurrent memory management and JIT compilation, where the Ion Engine's optimization processes interact with the garbage collector in an unsafe manner.
The operational impact of CVE-2023-5172 extends beyond simple browser instability, as it provides a potential pathway for remote code execution. Attackers could craft malicious JavaScript payloads that trigger the vulnerable hashtable mutation scenario, leading to memory corruption that can be leveraged for privilege escalation or system compromise. The vulnerability's exploitability is enhanced by the fact that it operates within the browser's core JavaScript execution environment, where attackers can easily deliver malicious content through web pages or email attachments. This makes it particularly dangerous in environments where users frequently browse untrusted websites or receive email with embedded content.
Mitigation strategies for CVE-2023-5172 primarily focus on immediate version upgrades to Firefox 118 or later, which contain patches addressing the hashtable mutation race condition. Organizations should implement comprehensive patch management procedures to ensure all browser installations are updated promptly. Additionally, browser hardening measures such as enabling sandboxing features, restricting JavaScript execution in sensitive contexts, and implementing content security policies can provide defense-in-depth. The vulnerability also highlights the importance of regular security assessments for JIT compilers and memory management systems, as similar issues may exist in other browser engines or software components that rely on similar optimization techniques. This vulnerability serves as a reminder of the critical security implications inherent in modern browser architectures where performance optimization meets memory safety requirements.