CVE-2026-103399
Fixed in a distro release EPSS <1%CVSS 5.3
A flaw was found in SoupServer (libsoup). When an HTTP/1.x client sends a request with Expect: 100-continue and a request body, and SoupServer returns an early final (non-1xx) response before the body is read, the server neither drains the declared body bytes nor closes the connection. On a keep-alive connection, those leftover bytes are interpreted as a subsequent HTTP request. A remote, unauthenticated attacker can place a complete HTTP request in the body and cause SoupServer to process that smuggled request, leading to unintended request handling.
Products: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 12 | libsoup2.4 | no fix |
| Debian 12 | libsoup3 | no fix |
| Debian 13 | libsoup2.4 | no fix |
| Debian 13 | libsoup3 | no fix |
| Debian 14 | libsoup3 | 3.8.0-1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Micro 5.3 | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Micro 5.4 | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Micro 5.5 | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | libsoup2 | 2.74.3-150600.4.42.1 |
| SUSE Linux Enterprise Server 12 SP5-LTSS | libsoup | 2.62.2-5.49.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | libsoup2 | 2.74.3-150600.4.42.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | libsoup | 2.62.2-5.49.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | libsoup2 | 2.74.3-150400.3.43.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | libsoup2 | 2.74.3-150600.4.42.1 |
| Ubuntu 22.04 LTS | libsoup2.4 | no fix |
| Ubuntu 24.04 LTS | libsoup2.4 | no fix |
| Ubuntu 24.04 LTS | libsoup3 | no fix |
| Ubuntu 26.04 LTS | libsoup3 | no fix |
| Ubuntu 26.10 | libsoup2.4 | no fix |
| Ubuntu 26.10 | libsoup3 | no fix |
| Ubuntu Pro 16.04 LTS | libsoup2.4 | no fix |
| Ubuntu Pro 18.04 LTS | libsoup2.4 | no fix |
| Ubuntu Pro 20.04 LTS | libsoup2.4 | no fix |
| Ubuntu Pro 22.04 LTS | libsoup3 | no fix |
| Ubuntu Pro 26.04 LTS | libsoup2.4 | no fix |
| openSUSE Tumbleweed | libsoup2 | 2.74.3-25.1 |