CVE-2010-0159 in Firefox
Summary
by MITRE
The browser engine in Mozilla Firefox 3.0.x before 3.0.18 and 3.5.x before 3.5.8, Thunderbird before 3.0.2, and SeaMonkey before 2.0.3 allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via vectors related to the nsBlockFrame::StealFrame function in layout/generic/nsBlockFrame.cpp, and unspecified other vectors.
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Analysis
by VulDB Data Team • 05/01/2026
The vulnerability identified as CVE-2010-0159 represents a critical memory corruption flaw affecting multiple Mozilla-based applications including Firefox, Thunderbird, and SeaMonkey. This vulnerability resides within the browser engine's handling of block frame elements during layout processing, specifically in the nsBlockFrame::StealFrame function located in layout/generic/nsBlockFrame.cpp. The flaw manifests when processing malformed or specially crafted web content that triggers improper memory management during frame reconstruction operations.
The technical nature of this vulnerability places it squarely within CWE-121, which describes heap-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read errors. These classifications indicate that the vulnerability stems from improper bounds checking during memory allocation and deallocation processes within the browser's rendering engine. The flaw allows attackers to manipulate memory structures through carefully constructed input that causes the application to read or write beyond allocated memory boundaries, leading to unpredictable behavior.
Operational impact of this vulnerability extends beyond simple denial of service to potentially enabling remote code execution. When exploited, the memory corruption can cause application crashes, browser instability, and in some cases, allow attackers to execute arbitrary code with the privileges of the affected user. The vulnerability affects multiple versions across different product lines, making it particularly dangerous as it requires users to maintain updated software across various Mozilla applications. The unspecified other vectors suggest that this flaw may have multiple exploitation paths, increasing the attack surface and complicating defensive measures.
Attackers can leverage this vulnerability by crafting malicious web pages or email content that, when processed by the affected applications, triggers the flawed memory management code. The exploit chain typically involves delivering malicious content through web browsers or email clients, where the targeted application's layout engine processes the malformed content and triggers the memory corruption. This aligns with ATT&CK technique T1203, which covers exploitation for privilege escalation through memory corruption vulnerabilities, and T1190, which describes the use of vulnerabilities in web browsers to execute malicious code.
Mitigation strategies for CVE-2010-0159 primarily focus on immediate software updates and patches provided by Mozilla. Organizations should prioritize updating all affected versions to their patched releases, specifically Firefox 3.0.18 and 3.5.8, Thunderbird 3.0.2, and SeaMonkey 2.0.3. Additionally, implementing browser hardening measures such as disabling JavaScript for untrusted content, using sandboxing techniques, and deploying web application firewalls can provide additional layers of protection. Network-based detection measures should monitor for suspicious web content patterns that may indicate exploitation attempts, while endpoint protection solutions should be configured to alert on unusual memory access patterns or application crashes that could indicate exploitation of this vulnerability.