CVE-2020-6825 in Firefox
Summary
by MITRE
Mozilla developers and community members Tyson Smith and Christian Holler reported memory safety bugs present in Firefox 74 and Firefox ESR 68.6. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 68.7.0, Firefox ESR < 68.7, and Firefox < 75.
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Analysis
by VulDB Data Team • 05/06/2025
This vulnerability represents a critical memory safety issue discovered in Mozilla Firefox and Thunderbird products, specifically affecting versions prior to 75.0 and 68.7.0 respectively. The flaw was identified through collaborative efforts between Mozilla developers and community researchers, with Tyson Smith and Christian Holler contributing to the discovery process. These memory safety bugs constitute a significant security concern as they demonstrate evidence of memory corruption that could potentially be exploited by malicious actors to execute arbitrary code on affected systems.
The technical nature of this vulnerability lies in memory safety flaws that can lead to unpredictable behavior within the browser's memory management systems. Memory corruption vulnerabilities typically occur when applications fail to properly manage memory allocation and deallocation, allowing attackers to manipulate memory contents in ways that could lead to code execution. These specific bugs were found in Firefox version 74 and Firefox ESR 68.6, with the vulnerability extending to Thunderbird versions below 68.7.0 and Firefox ESR versions below 68.7. The presence of memory corruption evidence suggests that these flaws could have been leveraged for remote code execution attacks, making them particularly dangerous in the context of web browser security.
The operational impact of this vulnerability extends across multiple Mozilla products and represents a substantial risk to users of affected versions. The vulnerability affects both regular Firefox releases and the Extended Support Release (ESR) versions, indicating that organizations relying on long-term support versions are equally at risk. The potential for arbitrary code execution means that attackers could potentially gain full control of affected systems, leading to data theft, system compromise, or deployment of additional malware. This type of vulnerability is particularly concerning in enterprise environments where browsers are frequently targeted as initial attack vectors due to their widespread use and privileged access to system resources.
Organizations and users should immediately update to the patched versions of affected software to mitigate this risk. The vulnerability aligns with common CWE categories related to memory safety issues such as CWE-122 (Heap Overflow) and CWE-787 (Out-of-bounds Write), which are frequently targeted by attackers in browser exploitation campaigns. From an ATT&CK framework perspective, this vulnerability could be leveraged in techniques such as T1059 (Command and Scripting Interpreter) and T1074 (Data Staged) to establish persistent access and exfiltrate information. The remediation strategy should include immediate patch deployment across all affected systems, along with monitoring for potential exploitation attempts. Security teams should also implement network-level controls and browser hardening measures to reduce the attack surface, while maintaining awareness of similar vulnerabilities in other browser components that may present analogous risks.