Description
A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).
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 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 | 3.6.6-1ubuntu3 | USN-8890-2 |
| Ubuntu 26.04 LTS | libsoup3 | 3.6.6-1ubuntu0.1 | USN-8890-1 |
| Ubuntu 25.10 | libsoup3 | No fix yet | — |
| Ubuntu 24.04 LTS | libsoup2.4 | 2.74.3-6ubuntu1.9 | USN-8890-1 |
| Ubuntu 24.04 LTS | libsoup3 | 3.4.4-5ubuntu0.9 | USN-8890-1 |
| Ubuntu 22.04 LTS | libsoup2.4 | 2.74.2-3ubuntu0.9 | USN-8890-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | libsoup2.4 | 2.74.3-10.1ubuntu5+esm3 | USN-8890-1 |
| Ubuntu Pro 22.04 LTS | libsoup3 | 3.0.7-0ubuntu1+esm9 | USN-8890-1 |
| Ubuntu Pro 20.04 LTS | libsoup2.4 | 2.70.0-1ubuntu0.5+esm4 | USN-8890-1 |
| Ubuntu Pro 18.04 LTS | libsoup2.4 | 2.62.1-1ubuntu0.4+esm9 | USN-8890-1 |
| Ubuntu Pro 16.04 LTS | libsoup2.4 | 2.52.2-1ubuntu0.3+esm8 | USN-8890-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | libsoup3 +2 | 3.6.5-3.el10_1.11 | RHSA-2026:19143, RHSA-2026:15968 |
Show 1 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_0.15 | RHSA-2026:17482 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | libsoup3 +1 | 3.6.5-3.el10_2.11 | ALSA-2026:19143 |
| AlmaLinux 10 | libsoup3-doc | 3.6.5-3.el10_1.11 | ALSA-2026:19143, ALSA-2026:15968 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | libsoup3 | 3.6.5-3.el10_1.11 | RLSA-2026:15968 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | libsoup | 3.4.4-150600.3.47.1 | SUSE-SU-2026:2314-1 |
| SLES 15 SP6 | libsoup | 3.4.4-150600.3.47.1 | SUSE-SU-2026:2314-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | libsoup | 3.6.6-160000.2.1 | SUSE-SU-2026:21998-1 |
| SLES for SAP 15 SP6 | libsoup | 3.4.4-150600.3.47.1 | SUSE-SU-2026:2314-1 |
| SLES 16.0 | libsoup | 3.6.6-160000.2.1 | SUSE-SU-2026:21998-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libsoup | 3.6.6-5.1 | openSUSE-SU-2026:10911-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | libsoup3 +2 | 3.6.5-3.el10_1.11 | ELSA-2026-19143, ELSA-2026-15968 |
Advisories 14
- ALSA-2026:19143 Moderate: libsoup3 security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2026:15968 Moderate: libsoup3 security update AlmaLinux Security Advisories · Oct 29, 2026
- WID-SEC-2026-1007 IBM App Connect Enterprise: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 25, 2026
- USN-8890-2 libsoup3 vulnerabilities Ubuntu Security Notices (USN) · Oct 22, 2026
- USN-8890-1 libsoup2.4, libsoup3 vulnerabilities Ubuntu Security Notices (USN) · Oct 7, 2026
- RHSA-2026:19143 Red Hat Security Advisory: libsoup3 security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:17482 Red Hat Security Advisory: libsoup3 security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- RHSA-2026:15968 Red Hat Security Advisory: libsoup3 security update Red Hat Security Advisories (RHSA) · Oct 3, 2026
- ELSA-2026-19143 Moderate: libsoup3 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Jul 16, 2026
- SUSE-SU-2026:2314-1 Security update for libsoup SUSE / openSUSE Security Updates · Jun 10, 2026
- SUSE-SU-2026:21998-1 Security update for libsoup SUSE / openSUSE Security Updates · Jun 9, 2026
- openSUSE-SU-2026:10911-1 libsoup-3_0-0-3.6.6-5.1 on GA media SUSE / openSUSE Security Updates · May 31, 2026
- RLSA-2026:15968 Moderate: libsoup3 security update Rocky Linux Security Advisories · May 13, 2026
- ELSA-2026-15968 Moderate: libsoup3 security update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · May 11, 2026
References
- RHSA-2026:15968 vendor-advisory
- RHSA-2026:17482 vendor-advisory
- RHSA-2026:19143 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-4271 vdb-entry
- RHBZ#2448044 issue-tracking
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/496