CVE-2008-2801 in Firefox
Summary
by MITRE
Mozilla Firefox before 2.0.0.15 and SeaMonkey before 1.1.10 do not properly implement JAR signing, which allows remote attackers to execute arbitrary code via (1) injection of JavaScript into documents within a JAR archive or (2) a JAR archive that uses relative URLs to JavaScript files.
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Analysis
by VulDB Data Team • 08/12/2019
The vulnerability described in CVE-2008-2801 represents a critical security flaw in the implementation of JAR (Java Archive) signing mechanisms within Mozilla Firefox versions prior to 2.0.0.15 and SeaMonkey versions prior to 1.1.10. This weakness stems from insufficient validation of JAR archive contents and their associated digital signatures, creating a pathway for malicious actors to bypass security controls that should prevent unauthorized code execution. The flaw specifically targets the browser's handling of signed JAR archives, which are commonly used to distribute web applications and extensions that require verification of their authenticity and integrity.
The technical implementation of this vulnerability occurs through two primary attack vectors that exploit the weak JAR signing validation. The first vector involves injection of JavaScript code directly into documents contained within JAR archives, allowing attackers to place malicious scripts within legitimate-looking archives that appear to be properly signed. The second vector leverages relative URLs within JAR archives to reference JavaScript files, enabling attackers to manipulate the execution flow by redirecting to malicious JavaScript resources that are not properly validated against the archive's signature. Both attack methods fundamentally undermine the trust model that JAR signing is designed to establish, as they allow code execution without proper verification of the archive's integrity or the authenticity of its contents.
The operational impact of this vulnerability extends beyond simple code execution, as it enables attackers to perform sophisticated attacks that can compromise user systems and data. When successful, these attacks can lead to complete system compromise, data theft, or the installation of persistent malware. The vulnerability is particularly dangerous because it operates at the browser level, where it can access user data, manipulate browser behavior, and potentially escalate privileges. The attack requires minimal user interaction since JAR archives are often automatically processed by browsers, making the exploitation process relatively straightforward for threat actors. This vulnerability affects a significant portion of users running older versions of Firefox and SeaMonkey, as these browsers were widely distributed and used in enterprise and personal environments.
Mitigation strategies for this vulnerability focus on immediate remediation through software updates and browser version upgrades to the patched versions that properly implement JAR signing validation. Organizations should prioritize updating their browser installations to ensure that the security patches are applied across all affected systems. Additionally, security administrators should implement network monitoring to detect and block suspicious JAR archive traffic, particularly those with unusual or untrusted origins. The vulnerability aligns with CWE-295, which addresses improper certificate validation, and can be mapped to ATT&CK techniques involving execution through web browsers and privilege escalation through malicious code injection. Users should also be educated about the risks of downloading and executing JAR archives from untrusted sources, and organizations should establish strict policies regarding the handling of signed archives within their environments to prevent exploitation of this and similar vulnerabilities.