Overview
CVE-2025-32906 is a critical vulnerability discovered in libsoup, a widely-used HTTP client/server library in C. If exploited, this flaw could allow a malicious actor to crash the HTTP server, potentially leading to a system compromise or data leakage. Given the severity of this flaw, it is crucial for affected systems to mitigate the risk as quickly as possible.
Vulnerability Summary
CVE ID: CVE-2025-32906
Severity: High (7.5 CVSS)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise, data leakage
Affected Products
Product | Affected Versions
libsoup | All versions prior to patch
How the Exploit Works
The vulnerability lies in the soup_headers_parse_request() function within the libsoup library. A malicious user could send a specially crafted HTTP request to trigger an out-of-bound read, causing the HTTP server to crash. This crash could potentially allow further exploitation, leading to system compromise and data leakage.
Conceptual Example Code
Below is a conceptual example of a malicious HTTP request that could exploit this vulnerability:
GET / HTTP/1.1
Host: target.example.com
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: close
Upgrade-Insecure-Requests: 1
If-Modified-Since: Thu, 01 Jan 1970 00:00:00 GMT
Cache-Control: max-age=0, no-cache, no-store, must-revalidate
Pragma: no-cache
In this example, specific combinations of headers or values may trigger the out-of-bound read, leading to a server crash.
Mitigation Guidance
Users of libsoup are strongly recommended to apply the vendor patch as soon as possible. In the meantime, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used as temporary mitigation to filter out malicious HTTP requests.
