CVE-2025-4476

MEDIUM

CVSS v3.1: 4.3 · EPSS: 0.0031 (22.5 percentile)

NetworkNo privilegesNULL Pointer Deref

Source data as of:

At a glance

Severity
MEDIUM
CVSS
4.3 v3.1 · NVD
EPSS
0.0031 (22.5 percentile) · FIRST.org
CISA KEV
No
Type
NULL Pointer Deref · NVD CWE
Attack conditions (CVSS vector)
NetworkNo privileges · Source: NVD Vector
Published
2025-05-16 · Modified: 2026-06-25

CVSS / EPSS / KEV

CVSS v3.1 4.3 / 10 MEDIUM Source: NVD
EPSS 0.0031 22.5 percentile Source: FIRST.org
CISA KEV No Source: CISA

Source — CVSS: NVD · EPSS: FIRST.org · KEV: CISA. Data & Sources

Description

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.

Record details

CVE ID
CVE-2025-4476
CVSS (v3.1)
4.3 (MEDIUM)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Exploitability subscore
2.8
Impact subscore
1.4
EPSS
0.0031 (22.5 percentile) — 2026-06-26
CISA KEV
No
Weakness (CWE)
CWE-476
Affected configurations (CPE)
0
Published
2025-05-16
Modified
2026-06-25
Status
Deferred

References

Reference URLs as listed by NVD, grouped by a mechanical match on the link's host/pattern. Labels describe the link type only.