CVE Catalog

CVE-2025-14523

HighCVSS 8.2
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.50%

39th percentile - higher than 39% of all known CVEs

Summary

A flaw in libsoup's HTTP header handling allows multiple Host: headers in a request, with the server processing the last one. Since front proxies often honor the first Host: header, this mismatch can cause vhost confusion.

Risk Assessment

An attacker can exploit this vulnerability for request smuggling, cache poisoning, or bypassing host-based access controls, potentially leading to unauthorized access to resources.

Recommendation

Update libsoup to a version that rejects requests with multiple Host: headers or processes only the first one. As a temporary workaround, configure the proxy to remove duplicate Host: headers.

Other vulnerabilities in libsoup

See all
Original NVD description (English source)

A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS