Security Advisory
CVE-2026-66338
5.4
MEDIUM
Vulnerability Description
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 characters. When libsoup operates behind a strict frontend proxy, this parsing differential can be exploited to smuggle HTTP requests.
Published Date
July 24, 2026
Official Source
NIST NVD Advisory