CVE-2007-5199 in libXfont
Summary
by MITRE
A single byte overflow in catalogue.c in X.Org libXfont 1.3.1 allows remote attackers to have unspecified impact.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 12/16/2022
The vulnerability identified as CVE-2007-5199 represents a critical buffer overflow flaw within the X.Org libXfont library version 1.3.1, specifically within the catalogue.c source file. This issue manifests as a single byte overflow, indicating a relatively small memory corruption vulnerability that can have severe consequences in networked environments. The flaw occurs during font catalogue processing operations, where improper input validation allows malicious data to overwrite adjacent memory locations. The vulnerability's remote exploitability means that attackers can potentially trigger this condition through network-based interactions with systems running affected software versions, making it particularly dangerous in server environments where X Window System services are exposed to external networks. The unspecified impact designation suggests that the consequences could range from denial of service to arbitrary code execution depending on the specific exploitation context and system configuration.
The technical nature of this vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions where insufficient bounds checking allows attackers to write beyond allocated memory regions. This type of vulnerability typically occurs when programs fail to validate input lengths before copying data into fixed-size buffers, creating opportunities for attackers to manipulate memory layout and potentially execute malicious code. The single byte overflow characteristic indicates that the vulnerability may be exploitable through precise memory corruption techniques that can alter control flow instructions or data structures within the application memory space. The X.Org libXfont library serves as a fundamental component in X Window System implementations, making this vulnerability particularly concerning as it could affect a wide range of Unix-like operating systems and applications that depend on proper font handling functionality.
From an operational perspective, the impact of CVE-2007-5199 extends beyond simple service disruption, potentially enabling sophisticated attack vectors that align with techniques described in the MITRE ATT&CK framework under the Tactic of Execution and Privilege Escalation. Systems utilizing affected X.Org libXfont versions could experience complete system compromise if attackers successfully exploit this vulnerability through remote access methods. The vulnerability's presence in a core system library means that exploitation could affect multiple applications and services that rely on font rendering capabilities, potentially providing attackers with a foothold for further lateral movement within network environments. Network administrators and security professionals must consider this vulnerability as part of broader security assessments, particularly in environments where X Window System services are accessible from untrusted networks or where privileged access to font processing functions might be available to attackers.
Mitigation strategies for CVE-2007-5199 should prioritize immediate software updates and patches from X.Org maintainers, as this vulnerability was addressed through code modifications that implement proper bounds checking and input validation. The recommended approach involves upgrading to libXfont versions that contain fixes for the catalogue.c buffer overflow condition, typically requiring version 1.4.0 or later depending on specific distribution packages. System administrators should also implement network segmentation and access controls to limit exposure of X Window System services to trusted networks only, reducing the attack surface available to potential exploiters. Additional defensive measures include monitoring for unusual network traffic patterns related to font processing operations and implementing intrusion detection systems that can identify potential exploitation attempts targeting this specific vulnerability. The vulnerability's classification as a remote code execution risk necessitates comprehensive security audits of all systems running affected software versions, with particular attention to systems that expose X11 services to external networks or that process untrusted font data from network sources.