CVE-2007-5807 in Ultra Star Reader
Summary
by MITRE
Buffer overflow in the register function in Ultra Star Reader ActiveX control in SSReader allows remote attackers to execute arbitrary code via unspecified vectors, as exploited in the wild. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.
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Analysis
by VulDB Data Team • 07/29/2019
The vulnerability identified as CVE-2007-5807 represents a critical buffer overflow flaw within the Ultra Star Reader ActiveX control, specifically within its register function. This ActiveX component, part of the SSReader software suite, exposes a dangerous programming error that can be exploited by remote attackers to gain arbitrary code execution capabilities. The vulnerability resides in the software's handling of input data within the register function, where insufficient bounds checking allows malicious data to overwrite adjacent memory locations. Such buffer overflow conditions create exploitable memory corruption scenarios that can be leveraged by attackers to inject and execute malicious code on vulnerable systems. The attack vector is particularly concerning as it operates through remote exploitation without requiring local system access, making it highly attractive to threat actors seeking widespread compromise.
The technical implementation of this vulnerability demonstrates a classic buffer overflow pattern where the register function fails to properly validate or limit input data length before copying it into fixed-size memory buffers. This flaw aligns with CWE-121, which categorizes buffer overflow conditions occurring when insufficient bounds checking is performed during memory operations. The ActiveX control's architecture creates a particularly dangerous attack surface since it operates within web browsers, making exploitation possible through malicious web pages or crafted documents. Attackers can leverage this vulnerability by crafting specially designed input parameters that exceed the allocated buffer space, causing stack corruption that can be manipulated to redirect program execution flow. The lack of detailed information regarding the exact exploitation vectors suggests that multiple attack pathways may exist, potentially including web-based attacks, email attachments, or other delivery mechanisms that trigger the vulnerable ActiveX control.
The operational impact of CVE-2007-5807 extends beyond simple code execution, as it provides attackers with elevated privileges on compromised systems. The vulnerability's exploitation in the wild indicates that threat actors recognized its potential for serious damage, particularly in enterprise environments where ActiveX controls are often enabled for legitimate business applications. Systems running vulnerable versions of Ultra Star Reader software become potential entry points for more sophisticated attacks, including privilege escalation, data exfiltration, and persistent backdoor installation. The ActiveX control's integration with web browsers means that users may inadvertently trigger exploitation through normal browsing activities, making the attack surface extremely broad. Organizations with legacy systems or those maintaining older software versions face significant risk, as the vulnerability predates many modern security mitigations and defenses that would otherwise protect against such memory corruption attacks.
Mitigation strategies for CVE-2007-5807 must address both immediate remediation and long-term security posture improvements. The most effective immediate solution involves disabling or removing the vulnerable Ultra Star Reader ActiveX control from affected systems, particularly those with internet-facing applications or browsers. System administrators should implement browser security policies that prevent ActiveX controls from running automatically, and consider deploying application whitelisting solutions to restrict execution of known vulnerable components. The vulnerability's nature suggests that traditional stack protection mechanisms may not be sufficient, requiring organizations to implement modern exploit mitigations such as data execution prevention, address space layout randomization, and stack canaries. Organizations should also conduct comprehensive vulnerability assessments to identify other potentially vulnerable ActiveX controls or software components that may present similar risks. According to ATT&CK framework, this vulnerability maps to T1059.007 for execution through ActiveX controls, and T1068 for privilege escalation opportunities that may follow successful exploitation, emphasizing the need for layered defensive measures. Regular security updates and patch management processes should be strengthened to prevent similar vulnerabilities from being introduced through legacy components that are no longer supported or maintained by vendors.