This page tracks the Debian fix status. The vulnerability itself is described on the main CVE page.
View CVE-2026-66338 →
DEBIAN-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 viol...
Original description
The description as published by the source.
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.
Source: OSV.dev (Open Source Vulnerabilities) OSV
Affected packages
Debian:12
libsoup2.4
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Debian:13
libsoup2.4
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Debian:12
libsoup3
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Debian:13
libsoup3
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Debian:14
libsoup3
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
References
- advisory security-tracker.debian.org