Description
A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 8.2 Advanced Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Telecommunications Update Service | — | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Extended Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
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 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | libsoup3 +2 | 3.6.5-3.el10_1.8 | RHSA-2026:0423 |
| RHEL 9 | libsoup +1 | 2.72.0-12.el9_7.3 | RHSA-2026:0422 |
| RHEL 8 | libsoup +1 | 2.62.3-11.el8_10 | RHSA-2026:0421 |
| RHEL 8 | spice-client-win +2 | 8.10-6.el8_10.1 | RHSA-2026:1509 |
Show 14 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | libsoup3 +2 | 3.6.5-3.el10_0.11 | RHSA-2026:0836 |
| RHEL 9.6 EUS | libsoup +1 | 2.72.0-10.el9_6.5 | RHSA-2026:0907 |
| RHEL 9.4 EUS | libsoup +1 | 2.72.0-8.el9_4.8 | RHSA-2026:0908 |
| RHEL 9.2 E4S | libsoup +1 | 2.72.0-8.el9_2.8 | RHSA-2026:0868 |
| RHEL 9.0 E4S | libsoup +1 | 2.72.0-8.el9_0.8 | RHSA-2026:0906 |
| RHEL 8.8 TUS | libsoup +1 | 2.62.3-3.el8_8.7 | RHSA-2026:0867 |
| RHEL 8.8 TUS | spice-client-win +2 | 8.10-6.el8_8.1 | RHSA-2026:1569 |
| RHEL 8.8 E4S | libsoup +1 | 2.62.3-3.el8_8.7 | RHSA-2026:0867 |
| RHEL 8.8 E4S | spice-client-win +2 | 8.10-6.el8_8.1 | RHSA-2026:1569 |
| RHEL 8.6 TUS | libsoup +1 | 2.62.3-2.el8_6.7 | RHSA-2026:0905 |
| RHEL 8.6 TUS | spice-client-win +2 | 8.10-6.el8_6.1 | RHSA-2026:1570 |
| RHEL 8.6 E4S | libsoup +1 | 2.62.3-2.el8_6.7 | RHSA-2026:0905 |
| RHEL 8.6 E4S | spice-client-win +2 | 8.10-6.el8_6.1 | RHSA-2026:1570 |
| RHEL 8.6 AUS | libsoup +1 | 2.62.3-2.el8_6.7 | RHSA-2026:0905 |
| RHEL 8.6 AUS | spice-client-win +2 | 8.10-6.el8_6.1 | RHSA-2026:1570 |
| RHEL 8.4 EUS Long Life | libsoup +1 | 2.62.3-2.el8_4.7 | RHSA-2026:0909 |
| RHEL 8.4 EUS Long Life | spice-client-win +2 | 8.10-6.el8_4.1 | RHSA-2026:1572 |
| RHEL 8.4 AUS | libsoup +1 | 2.62.3-2.el8_4.7 | RHSA-2026:0909 |
| RHEL 8.4 AUS | spice-client-win +2 | 8.10-6.el8_4.1 | RHSA-2026:1572 |
| RHEL 8.2 AUS | libsoup +1 | 2.62.3-1.el8_2.7 | RHSA-2026:0911 |
| RHEL 8.2 AUS | spice-client-win +2 | 8.10-6.el8_2.1 | RHSA-2026:1571 |
| RHEL 7 ELS | libsoup +1 | 2.62.2-10.el7_9 | RHSA-2026:0925 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | libsoup3-doc | 3.6.5-3.el10_1.8 | ALSA-2026:0423 |
| AlmaLinux 9 | libsoup +1 | 2.72.0-12.el9_7.3 | ALSA-2026:0422 |
| AlmaLinux 8 | libsoup +1 | 2.62.3-11.el8_10 | ALSA-2026:0421 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | libsoup3 | 3.6.5-3.el10_1.8 | RLSA-2026:0423 |
| Rocky Linux 9 | libsoup | 2.72.0-12.el9_7.3 | RLSA-2026:0422 |
| Rocky Linux 8 | libsoup | 2.62.3-11.el8_10 | RLSA-2026:0421 |
| Rocky Linux 8 | spice-client-win | 8.10-6.el8_10.1 | RLSA-2026:1509 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | libsoup | 3.4.4-150600.3.28.1 | SUSE-SU-2026:0257-1 |
| SLES 15 SP7 | libsoup2 | 2.74.3-150600.4.19.1 | SUSE-SU-2026:0253-1 |
| SLES 15 SP6 | libsoup | 3.4.4-150600.3.28.1 | SUSE-SU-2026:0257-1 |
| SLES 15 SP6 | libsoup2 | 2.74.3-150600.4.19.1 | SUSE-SU-2026:0253-1 |
| SLES 15 SP5 | libsoup | 3.0.4-150400.3.28.1 | SUSE-SU-2026:0211-1 |
| SLES 15 SP5 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLES 15 SP4 | libsoup | 3.0.4-150400.3.28.1 | SUSE-SU-2026:0211-1 |
| SLES 15 SP4 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLES 12 SP5 | libsoup | 2.62.2-5.23.1 | SUSE-SU-2026:0123-1 |
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 | 3.4.4-150600.3.28.1 | SUSE-SU-2026:0257-1 |
| SLES for SAP 15 SP6 | libsoup2 | 2.74.3-150600.4.19.1 | SUSE-SU-2026:0253-1 |
| SLES for SAP 15 SP5 | libsoup | 3.0.4-150400.3.28.1 | SUSE-SU-2026:0211-1 |
| SLES for SAP 15 SP5 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLES for SAP 15 SP4 | libsoup | 3.0.4-150400.3.28.1 | SUSE-SU-2026:0211-1 |
| SLES for SAP 15 SP4 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| 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_6.1 | SUSE-SU-2026:20360-1 |
| SLE Micro 6.0 | libsoup | 3.4.2-10.1 | SUSE-SU-2026:20053-1 |
| SLE Micro 5.5 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLE Micro 5.4 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLE Micro 5.3 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLE Micro 5.2 | libsoup | 2.68.4-150200.4.19.1 | SUSE-SU-2026:0151-1 |
| SLE HPC 15 SP5 | libsoup | 3.0.4-150400.3.28.1 | SUSE-SU-2026:0211-1 |
| SLE HPC 15 SP5 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
| SLE HPC 15 SP4 | libsoup | 3.0.4-150400.3.28.1 | SUSE-SU-2026:0211-1 |
| SLE HPC 15 SP4 | libsoup2 | 2.74.2-150400.3.19.1 | SUSE-SU-2026:3936-1, SUSE-SU-2026:0258-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libsoup | 3.6.5-10.1 | openSUSE-SU-2026:10023-1 |
| openSUSE Tumbleweed | libsoup2 | 2.74.3-13.1 | openSUSE-SU-2026:10024-1 |
| 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 | 3.4.4-150600.3.28.1 | SUSE-SU-2026:0257-1 |
| openSUSE Leap 15.6 | libsoup2 | 2.74.3-150600.4.19.1 | SUSE-SU-2026:0253-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libsoup +2 | 2.72.0-6.amzn2023.0.10 | ALAS2023-2026-1391 |
| Amazon Linux 2023 | libsoup3 +2 | 3.6.5-55.amzn2023 | ALAS2023-2026-1394 |
| Amazon Linux 2 | libsoup +1 | 2.56.0-6.amzn2.0.7 | ALAS2-2026-3142 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | libsoup | 3.4.4-12 | — |
| Azure Linux 2 (CBL-Mariner) | libsoup | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | libsoup3 +2 | 3.6.5-3.el10_1.8 | ELSA-2026-0423 |
| Oracle Linux 9 | libsoup +1 | 2.72.0-12.el9_7.3 | ELSA-2026-0422 |
| Oracle Linux 8 | libsoup +1 | 2.62.3-11.el8_10 | ELSA-2026-0421 |
| Oracle Linux 7 | libsoup +1 | 2.62.2-2.0.9.el7 | ELSA-2026-0925 |
Advisories 49
- ALSA-2026:0422 Important: libsoup security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:0423 Important: libsoup3 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:0421 Important: libsoup security update AlmaLinux Security Advisories · Oct 29, 2026
- WID-SEC-2026-0062 Red Hat Enterprise Linux (libsoup): Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen und Datenmanipulation BSI CERT-Bund (WID) · Sep 17, 2026
- SUSE-SU-2026:3936-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Sep 10, 2026
- WID-SEC-2026-1730 Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Jul 16, 2026
- RHSA-2026:1572 Red Hat Security Advisory: spice-client-win security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:1571 Red Hat Security Advisory: spice-client-win security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:1569 Red Hat Security Advisory: spice-client-win security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:1570 Red Hat Security Advisory: spice-client-win security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:1509 Red Hat Security Advisory: spice-client-win security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0925 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0909 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0911 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0908 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0906 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0907 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0905 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0867 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0868 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0836 Red Hat Security Advisory: libsoup3 security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0422 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0423 Red Hat Security Advisory: libsoup3 security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2026:0421 Red Hat Security Advisory: libsoup security update Red Hat Security Advisories (RHSA) · Jun 30, 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-2026:10023-1 libsoup-3_0-0-3.6.5-10.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10024-1 libsoup-2_4-1-2.74.3-13.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20360-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20053-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0253-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0257-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0258-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0211-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0151-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0123-1 Security update for libsoup SUSE / openSUSE Security Updates · Mar 23, 2026
- ELSA-2026-0925 Important: libsoup security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Feb 11, 2026
- ALAS2-2026-3142 Important: libsoup security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Feb 5, 2026
- ALAS2023-2026-1391 Important: libsoup security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Feb 5, 2026
- ALAS2023-2026-1394 Important: libsoup3 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Feb 5, 2026
- RLSA-2026:1509 Important: spice-client-win security update Rocky Linux Security Advisories · Jan 30, 2026
- RLSA-2026:0423 Important: libsoup3 security update Rocky Linux Security Advisories · Jan 15, 2026
- RLSA-2026:0422 Important: libsoup security update Rocky Linux Security Advisories · Jan 15, 2026
- RLSA-2026:0421 Important: libsoup security update Rocky Linux Security Advisories · Jan 14, 2026
- ELSA-2026-0421 Important: libsoup security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jan 12, 2026
- ELSA-2026-0423 Important: libsoup3 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jan 12, 2026
- ELSA-2026-0422 Important: libsoup security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jan 12, 2026
References
- RHSA-2026:0421 vendor-advisory
- RHSA-2026:0422 vendor-advisory
- RHSA-2026:0423 vendor-advisory
- RHSA-2026:0836 vendor-advisory
- RHSA-2026:0867 vendor-advisory
- RHSA-2026:0868 vendor-advisory
- RHSA-2026:0905 vendor-advisory
- RHSA-2026:0906 vendor-advisory
- RHSA-2026:0907 vendor-advisory
- RHSA-2026:0908 vendor-advisory
- RHSA-2026:0909 vendor-advisory
- RHSA-2026:0911 vendor-advisory
- RHSA-2026:0925 vendor-advisory
- RHSA-2026:1509 vendor-advisory
- RHSA-2026:1569 vendor-advisory
- RHSA-2026:1570 vendor-advisory
- RHSA-2026:1571 vendor-advisory
- RHSA-2026:1572 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2025-14523 vdb-entry
- RHBZ#2421349 issue-tracking
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/472