Description
A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values.
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 | libsoup3 +1 | No fix yet | — |
| Ubuntu 26.04 LTS | libsoup3 | 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 | 3.4.4-150600.3.34.1 | SUSE-SU-2026:4631-1, SUSE-SU-2026:0690-1 |
| SLES 15 SP7 | libsoup2 | 2.74.3-150600.4.27.1 | SUSE-SU-2026:4703-1, SUSE-SU-2026:0657-1 |
| SLES 15 SP6 | libsoup | 3.4.4-150600.3.34.1 | SUSE-SU-2026:4631-1, SUSE-SU-2026:0690-1 |
| SLES 15 SP6 | libsoup2 | 2.74.3-150600.4.27.1 | SUSE-SU-2026:4703-1, SUSE-SU-2026:0657-1 |
| SLES 15 SP5 | libsoup | 3.0.4-150400.3.34.1 | SUSE-SU-2026:4616-1, SUSE-SU-2026:0689-1 |
| SLES 15 SP5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLES 15 SP4 | libsoup | 3.0.4-150400.3.34.1 | SUSE-SU-2026:4616-1, SUSE-SU-2026:0689-1 |
| SLES 15 SP4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLES 12 SP5 | libsoup | 2.62.2-5.34.1 | SUSE-SU-2026:0703-1 |
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 | 3.4.4-150600.3.34.1 | SUSE-SU-2026:4631-1, SUSE-SU-2026:0690-1 |
| SLES for SAP 15 SP6 | libsoup2 | 2.74.3-150600.4.27.1 | SUSE-SU-2026:4703-1, SUSE-SU-2026:0657-1 |
| SLES for SAP 15 SP5 | libsoup | 3.0.4-150400.3.34.1 | SUSE-SU-2026:4616-1, SUSE-SU-2026:0689-1 |
| SLES for SAP 15 SP5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLES for SAP 15 SP4 | libsoup | 3.0.4-150400.3.34.1 | SUSE-SU-2026:4616-1, SUSE-SU-2026:0689-1 |
| SLES for SAP 15 SP4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, 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 | 3.4.2-13.1 | SUSE-SU-2026:24368-1, SUSE-SU-2026:20529-1 |
| SLE Micro 5.5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLE Micro 5.4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLE Micro 5.3 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLE Micro 5.2 | libsoup | 2.68.4-150200.4.30.1 | SUSE-SU-2026:0658-1 |
| SLE HPC 15 SP5 | libsoup | 3.0.4-150400.3.34.1 | SUSE-SU-2026:4616-1, SUSE-SU-2026:0689-1 |
| SLE HPC 15 SP5 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
| SLE HPC 15 SP4 | libsoup | 3.0.4-150400.3.34.1 | SUSE-SU-2026:4616-1, SUSE-SU-2026:0689-1 |
| SLE HPC 15 SP4 | libsoup2 | 2.74.2-150400.3.31.1 | SUSE-SU-2026:4739-1, SUSE-SU-2026:0834-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libsoup | 3.6.6-1.1 | openSUSE-SU-2026:10245-1 |
| openSUSE Tumbleweed | libsoup2 | 2.74.3-17.1 | openSUSE-SU-2026:10246-1 |
| 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 | 3.4.4-150600.3.34.1 | SUSE-SU-2026:0690-1 |
| openSUSE Leap 15.6 | libsoup2 | 2.74.3-150600.4.27.1 | SUSE-SU-2026:0657-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libsoup3 +2 | 3.6.6-58.amzn2023 | ALAS2023-2026-1778 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | libsoup | 3.4.4-16 | — |
Advisories 20
- SUSE-SU-2026:24368-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 27, 2026
- SUSE-SU-2026:4739-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Oct 20, 2026
- SUSE-SU-2026:4703-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Oct 17, 2026
- SUSE-SU-2026:4631-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 13, 2026
- SUSE-SU-2026:4616-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 13, 2026
- ALAS2023-2026-1778 Moderate: libsoup3 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 8, 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
- openSUSE-SU-2026:20354-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10245-1 libsoup-3_0-0-3.6.6-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10246-1 libsoup-2_4-1-2.74.3-17.1 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-2026:0689-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0690-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0657-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0658-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0703-1 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-2026:20529-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 4, 2026