Medium [CVE-2025-4476] Libsoup: null pointer dereference in libsoup may lead to denial of service
This medium-severity Red Hat Linux advisory covers CVE-2025-4476 affecting Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published
Summary
A denial-of-service vulnerability has been identified in the libsoup HTTP client library. This flaw can be triggered when a libsoup client receives a 401 (Unauthorized) HTTP response containing a specifically crafted domain parameter within the WWW-Authenticate header.
Processing this malformed header can lead to a crash of the client application using libsoup. An attacker could exploit this by setting up a malicious HTTP server.
If a user's application using the vulnerable libsoup library connects to this malicious server, it could result in a denial-of-service. Successful exploitation requires tricking a user's client application into connecting to the attacker's malicious server.
The Red Hat Product Security team has assessed the severity of this vulnerability as Low. This determination is based on two key factors: successful exploitation necessitates a user being deceived into connecting to a malicious and untrusted HTTP server.
Furthermore, the impact of a successful attack is limited to crashing only the specific client instance actively communicating with that malicious service, preventing any widespread system-level repercussions by default. Weakness: CWE-476.
Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9.
Is CVE-2025-4476 exploited?
No exploitation is reported in the sources VulniPulse tracks: CVE-2025-4476 is not in the CISA KEV catalog (checked ) and this advisory does not report exploitation. That is not proof the vulnerability cannot be exploited.
How do I fix CVE-2025-4476?
The advisory VulniPulse tracks names no fixed release. Follow Red Hat's guidance for workarounds and updates.
Confirm against the vendor advisory before you patch.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative. Check it before change work.
Official advisory · high-confidence parse· fetched 4 days ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists. Confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 4 days ago·verify at source
Mitigation checklist
- To mitigate the risk posed by this libsoup vulnerability, Red Hat strongly advises against connecting client applications relying on the libsoup library to untrusted HTTP servers until systems can be updated to a version of libsoup that includes the fix for this specific flaw. This precaution will help prevent potential denial-of-service scenarios within user sessions.
Official advisory · high-confidence parse· fetched 4 days ago·verify at source
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