Vulnerability in GNOME Libsoup
CVE-2026-3632
A flaw was found in libsoup, a library used by applications to send network requests. This vulnerability occurs because libsoup does not properly validate hostnames, allowing special characters to be injected into HTTP headers. A remote attacker could exploit this to perform HTTP smuggling, where they can send hidden, malicious requests alongside legitimate ones. In certain situations, this could lead to Server-Side Request Forgery (SSRF), enabling an attacker to force the server to make unauthorized requests to other internal or external systems. The impact is low, as SoupServer is not actually used in internet infrastructure.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.9 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.003 (26.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-3632 (vdb-entry, Vendor Advisory)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Issue Tracking, Vendor Advisory)
- gitlab.gnome.org/GNOME/libsoup/-/issues/483 (Exploit, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-3632?
- CVE-2026-3632 is a low-severity vulnerability in GNOME Libsoup, classified under CWE-1286. CVSS score: 3.9/10. Published 2026-03-17.
- How severe is CVE-2026-3632?
- Low severity. CVSS v3 base score is 3.9 out of 10.