Description
A flaw was found in SoupServer. This HTTP request smuggling vulnerability occurs because SoupServer improperly handles requests that combine Transfer-Encoding: chunked and Connection: keep-alive headers. A remote, unauthenticated client can exploit this by sending specially crafted requests, causing SoupServer to fail to close the connection as required by RFC 9112. This allows the attacker to smuggle additional requests over the persistent connection, leading to unintended request processing and potential denial-of-service (DoS) conditions.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 13 | libsoup3 +1 | No fix yet | — |
| Debian 12 | libsoup3 +1 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | libsoup2.4 | No fix yet | — |
| Ubuntu 25.10 | libsoup3 +1 | No fix yet | — |
| Ubuntu 24.04 LTS | libsoup3 +1 | No fix yet | — |
| Ubuntu 22.04 LTS | libsoup2.4 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | libsoup2.4 | No fix yet | — |
| Ubuntu Pro 22.04 LTS | libsoup3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | libsoup2.4 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | libsoup2.4 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | libsoup2.4 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | libsoup | 3.4.4-150600.3.37.1 | SUSE-SU-2026:0788-1 |
| SLES 15 SP7 | libsoup2 | 2.74.3-150600.4.30.1 | SUSE-SU-2026:0811-1 |
| SLES 15 SP6 | libsoup | 3.4.4-150600.3.37.1 | SUSE-SU-2026:0788-1 |
| SLES 15 SP6 | libsoup2 | 2.74.3-150600.4.30.1 | SUSE-SU-2026:0811-1 |
| SLES 15 SP5 | libsoup | 3.0.4-150400.3.37.1 | SUSE-SU-2026:0833-1 |
| SLES 15 SP5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLES 15 SP4 | libsoup | 3.0.4-150400.3.37.1 | SUSE-SU-2026:0833-1 |
| SLES 15 SP4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLES 12 SP5 | libsoup | 2.62.2-5.37.1 | SUSE-SU-2026:0796-1 |
Show 14 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | libsoup | 3.6.6-160000.1.1 | SUSE-SU-2026:20902-1 |
| SLES for SAP 15 SP6 | libsoup | 3.4.4-150600.3.37.1 | SUSE-SU-2026:0788-1 |
| SLES for SAP 15 SP6 | libsoup2 | 2.74.3-150600.4.30.1 | SUSE-SU-2026:0811-1 |
| SLES for SAP 15 SP5 | libsoup | 3.0.4-150400.3.37.1 | SUSE-SU-2026:0833-1 |
| SLES for SAP 15 SP5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLES for SAP 15 SP4 | libsoup | 3.0.4-150400.3.37.1 | SUSE-SU-2026:0833-1 |
| SLES for SAP 15 SP4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLES 16.0 | libsoup | 3.6.6-160000.1.1 | SUSE-SU-2026:20902-1 |
| SLE Micro 6.2 | libsoup | 3.6.6-160000.1.1 | SUSE-SU-2026:20752-1 |
| SLE Micro 6.1 | libsoup | 3.4.4-slfo.1.1_7.1 | SUSE-SU-2026:20649-1 |
| SLE Micro 6.0 | libsoup | 3.4.2-14.1 | SUSE-SU-2026:20727-1 |
| SLE Micro 5.5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLE Micro 5.4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLE Micro 5.3 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLE Micro 5.2 | libsoup | 2.68.4-150200.4.33.1 | SUSE-SU-2026:0792-1 |
| SLE HPC 15 SP5 | libsoup | 3.0.4-150400.3.37.1 | SUSE-SU-2026:0833-1 |
| SLE HPC 15 SP5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
| SLE HPC 15 SP4 | libsoup | 3.0.4-150400.3.37.1 | SUSE-SU-2026:0833-1 |
| SLE HPC 15 SP4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:0834-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libsoup | 3.6.6-2.1 | openSUSE-SU-2026:10276-1 |
| openSUSE Tumbleweed | libsoup2 | 2.74.3-18.1 | openSUSE-SU-2026:10291-1 |
| openSUSE Leap 16.0 | libsoup | 3.6.6-160000.1.1 | openSUSE-SU-2026:20384-1 |
| openSUSE Leap 16.0 | libsoup2 | 2.74.3-160000.4.1 | openSUSE-SU-2026:20354-1 |
| openSUSE Leap 15.6 | libsoup | 3.4.4-150600.3.37.1 | SUSE-SU-2026:0788-1 |
| openSUSE Leap 15.6 | libsoup2 | 2.74.3-150600.4.30.1 | SUSE-SU-2026:0811-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libsoup +2 | 2.72.0-6.amzn2023.0.12 | ALAS2023-2026-1758 |
| Amazon Linux 2023 | libsoup3 +2 | 3.6.6-58.amzn2023 | ALAS2023-2026-1778 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | libsoup | 3.4.4-12 | — |
| Azure Linux 2 (CBL-Mariner) | libsoup | No fix yet | — |
Advisories 16
- ALAS2023-2026-1778 Moderate: libsoup3 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 8, 2026
- ALAS2023-2026-1758 Moderate: libsoup security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · May 26, 2026
- SUSE-SU-2026:20902-1 Security update for libsoup SUSE / openSUSE Security Updates · Apr 2, 2026
- openSUSE-SU-2026:20384-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 26, 2026
- SUSE-SU-2026:20752-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 25, 2026
- SUSE-SU-2026:20727-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 24, 2026
- openSUSE-SU-2026:20354-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10276-1 libsoup-3_0-0-3.6.6-2.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10291-1 libsoup-2_4-1-2.74.3-18.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20649-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0834-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 7, 2026
- SUSE-SU-2026:0833-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 6, 2026
- SUSE-SU-2026:0811-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 5, 2026
- SUSE-SU-2026:0796-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 4, 2026
- SUSE-SU-2026:0788-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 4, 2026
- SUSE-SU-2026:0792-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 4, 2026