CVE-2025-8197 in libsoup
Summary
by MITRE • 07/25/2025
A global buffer overflow vulnerability was found in the soup_header_name_to_string function in Libsoup. The `soup_header_name_to_string` function does not validate the `name` parameter passed in, and directly accesses `soup_header_name_strings[name]`. The value of `name` is controllable, when `name` exceeds the index range of `soup_headr_name_string`, it will cause an out-of-bounds access.
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Analysis
by VulDB Data Team • 08/14/2025
The vulnerability under examination represents a critical buffer overflow condition within the libsoup library's soup_header_name_to_string function, which operates as a fundamental component in HTTP header processing for numerous applications and services. This flaw constitutes a classic example of improper input validation where the function fails to enforce bounds checking on user-controllable parameters before accessing array elements. The vulnerability arises from the direct indexing operation soup_header_name_strings[name] without prior verification of whether the name parameter falls within the legitimate array boundaries, creating an exploitable condition that can lead to arbitrary code execution or system compromise.
The technical implementation of this vulnerability demonstrates a clear violation of secure coding practices and can be categorized under CWE-121 as a stack-based buffer overflow or CWE-787 as an out-of-bounds write condition. When an attacker supplies a malicious value for the name parameter that exceeds the valid index range of the soup_header_name_strings array, the function attempts to access memory locations outside the allocated buffer space. This out-of-bounds access can result in memory corruption, potentially allowing attackers to overwrite critical program data, execute arbitrary code, or cause application crashes and denial of service conditions. The vulnerability's impact is amplified by the fact that it operates at a foundational level within HTTP processing libraries, affecting numerous applications that depend on libsoup for network communications.
From an operational perspective, this vulnerability presents significant risks across multiple attack vectors as defined by the MITRE ATT&CK framework under T1203 (Exploitation for Client Execution) and T1059 (Command and Scripting Interpreter). Applications utilizing libsoup for HTTP header parsing become susceptible to remote code execution when processing maliciously crafted HTTP requests containing oversized header names. The attack surface extends beyond individual applications to encompass entire network infrastructure components, web servers, proxy services, and client applications that rely on this library for proper HTTP protocol handling. Given the widespread adoption of libsoup in various software ecosystems, including GNOME applications, web browsers, and network utilities, the potential impact of exploitation spans across multiple system domains and operational environments.
Mitigation strategies should encompass immediate patching of affected libsoup versions to implement proper bounds checking and input validation before array access operations. Security engineers must also consider implementing runtime protections such as stack canaries, address space layout randomization, and data execution prevention mechanisms to reduce exploitability. Network-level defenses including intrusion detection systems and web application firewalls should be configured to monitor for suspicious HTTP header patterns that might indicate exploitation attempts. Additionally, developers should adopt defensive programming practices such as using safe string handling functions, implementing comprehensive input validation routines, and conducting regular security code reviews to prevent similar vulnerabilities from emerging in future implementations. The vulnerability serves as a prime example of why adherence to secure coding standards and regular security assessments are essential for maintaining robust software security postures across complex application ecosystems.