CVE-2025-8035 in Thunderbird
Summary
by MITRE • 07/23/2025
Memory safety bugs present in Firefox ESR 128.12, Thunderbird ESR 128.12, Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. 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 Firefox < 141, Firefox ESR < 128.13, Firefox ESR < 140.1, Thunderbird < 141, Thunderbird < 128.13, and Thunderbird < 140.1.
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Analysis
by VulDB Data Team • 08/09/2025
The vulnerability identified as CVE-2025-8035 represents a critical memory safety issue affecting multiple Mozilla products including Firefox and Thunderbird across several versions. This vulnerability stems from memory safety bugs present in Firefox ESR 128.12, Thunderbird ESR 128.12, Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140, and Thunderbird 140. The presence of memory corruption evidence within these bugs indicates a fundamental flaw in how these applications handle memory allocation and deallocation processes. According to cybersecurity standards, such memory safety issues fall under CWE-119, which encompasses memory safety vulnerabilities including buffer overflows, use-after-free errors, and other memory corruption conditions that can lead to arbitrary code execution.
The technical exploitation of these memory safety bugs presents a significant operational risk to affected systems. When memory corruption occurs in browser applications, it creates opportunities for attackers to manipulate program execution flow and potentially gain unauthorized control over affected systems. The vulnerability's impact extends across multiple product lines and versions, affecting not only the standard Firefox and Thunderbird releases but also their extended support releases that are commonly used in enterprise environments. These memory safety flaws can be leveraged by threat actors to execute malicious code remotely, particularly when users interact with malicious web content or email attachments. The vulnerability's presence in both regular and extended support releases indicates that organizations using legacy versions of these applications face heightened risk exposure, as these versions may not receive timely security updates.
Organizations affected by CVE-2025-8035 should prioritize immediate mitigation through software updates to the latest available versions of Firefox and Thunderbird. The affected versions include Firefox < 141, Firefox ESR < 128.13, Firefox ESR < 140.1, Thunderbird < 141, Thunderbird < 128.13, and Thunderbird < 140.1, representing a broad spectrum of software versions that require urgent attention. According to ATT&CK framework category T1059, which covers command and control techniques, these vulnerabilities could enable attackers to establish persistent access through arbitrary code execution capabilities. Security administrators should implement network monitoring to detect potential exploitation attempts and consider deploying additional security controls such as web application firewalls and email filtering solutions. The vulnerability's classification under memory safety standards makes it particularly concerning for enterprise environments where these applications are widely deployed, as successful exploitation could lead to complete system compromise and data exfiltration.