CVE-2013-3667 in Yojimbo
Summary
by MITRE
The software update mechanism as used in Bare Bones Software Yojimbo before 4.0, TextWrangler before 4.5.3, and BBEdit before 10.5.5 does not properly download and verify updates before installation, which allows attackers to perform "tampering or corruption" of the updates.
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Analysis
by VulDB Data Team • 03/04/2019
The vulnerability identified as CVE-2013-3667 affects the software update mechanisms of several Bare Bones Software applications including Yojimbo before version 4.0, TextWrangler before version 4.5.3, and BBEdit before version 10.5.5. This represents a critical security flaw in the update verification process that directly impacts the integrity of software installations. The vulnerability stems from insufficient validation procedures during the software update download and installation phases, creating an exploitable gap in the application's security posture. According to CWE-20, this corresponds to improper input validation where the software fails to properly validate the integrity and authenticity of update files before executing them. The flaw enables attackers to manipulate update packages through tampering or corruption techniques that bypass normal security controls.
The technical implementation of this vulnerability occurs within the software update infrastructure where cryptographic verification mechanisms are either absent or improperly implemented. Attackers can exploit this weakness by intercepting update traffic or by directly replacing legitimate update files with malicious payloads. The absence of proper digital signatures or checksum validation means that compromised update packages can be seamlessly installed without detection by the affected applications. This vulnerability aligns with ATT&CK technique T1027 which describes the modification of binaries to evade detection, and T1059 which encompasses the execution of malicious code through compromised update mechanisms. The update process typically involves downloading files from remote servers, and without proper verification, these downloads can be manipulated to include malicious code that executes with the privileges of the target application.
The operational impact of CVE-2013-3667 extends beyond simple software corruption, representing a significant risk to system security and data integrity. When attackers successfully compromise update mechanisms, they can execute arbitrary code on target systems, potentially leading to complete system compromise. The vulnerability affects users who rely on automatic update mechanisms, as these systems can unknowingly install malicious code without user intervention. The affected applications typically run with elevated privileges during installation, amplifying the potential damage from successful exploitation. Organizations using these applications face increased risk of malware deployment, credential theft, and persistent backdoor establishment. The vulnerability also impacts the broader software ecosystem by undermining trust in update mechanisms and potentially enabling supply chain attacks where legitimate applications become vectors for malicious code delivery.
Mitigation strategies for CVE-2013-3667 require immediate attention through patching and implementation of additional security controls. Users should immediately upgrade to the patched versions of the affected software as provided by Bare Bones Software, with Yojimbo 4.0, TextWrangler 4.5.3, and BBEdit 10.5.5 representing the minimum required versions. Organizations should implement network monitoring to detect suspicious update traffic and establish secure update channels with proper certificate validation. The implementation of software integrity checking mechanisms, including digital signature verification and cryptographic checksum validation, should be enforced across all update processes. Additional defensive measures include network segmentation to limit update access, implementation of secure proxy configurations, and regular security audits of update mechanisms. According to industry best practices and NIST guidelines, organizations should also maintain updated inventories of installed software versions and implement automated patch management systems to prevent exploitation of known vulnerabilities. The vulnerability demonstrates the critical importance of maintaining secure update mechanisms and proper input validation in software development processes to prevent exploitation through supply chain attacks.