What is CVE-2026-66338?

CVE-2026-66338 is a medium-severity vulnerability in Red Hat Enterprise Linux 10, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 5.4/10. Published 2026-07-24.

How severe is CVE-2026-66338?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Vulnerability in Red Hat Enterprise Linux 10

CVE-2026-66338

A flaw was found in libsoup. The chunked transfer encoding parser uses a permissive parsing function for chunk sizes that silently accepts inputs violating RFC 9112, including leading whitespace, plus sign prefixes, and trailing invalid ch…

Vulnerability class: HTTP Request Smuggling

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

CWE-444 — Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling)

References

secalert@redhat.com (x_refsource_REDHAT, vdb-entry)
secalert@redhat.com (x_refsource_REDHAT, issue-tracking)

Frequently asked questions

What is CVE-2026-66338?: CVE-2026-66338 is a medium-severity vulnerability in Red Hat Enterprise Linux 10, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 5.4/10. Published 2026-07-24.
How severe is CVE-2026-66338?: Medium severity. CVSS v3 base score is 5.4 out of 10.