Description
A vulnerability was found in libsoup's HTTP/2 protocol implementation. The library fails to correctly release memory context blocks under specific stream termination conditions, such as when an HTTP/2 connection encounters window exhaustion or explicit stream resets. A remote, unauthenticated attacker acting as a malicious network peer can trick the connection engine into allocating stream states that are subsequently leaked during cleanup. Over a sustained period, this flaw allows the remote attacker to consume the system's heap allocations incrementally, triggering a denial of service (DoS) through an ultimate Out-of-Memory (OOM) application crash.
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 | No fix yet | — |
| Ubuntu 26.04 LTS | libsoup3 | No fix yet | — |
| Ubuntu 24.04 LTS | libsoup3 | No fix yet | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 22.04 LTS | libsoup3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | libsoup | 3.4.4-150600.3.59.1 | SUSE-SU-2026:4631-1 |
| SLES 15 SP7 | libsoup2 | 2.74.3-150600.4.42.1 | SUSE-SU-2026:4703-1 |
| SLES 15 SP6 | libsoup | 3.4.4-150600.3.59.1 | SUSE-SU-2026:4631-1 |
| SLES 15 SP6 | libsoup2 | 2.74.3-150600.4.42.1 | SUSE-SU-2026:4703-1 |
| SLES 15 SP5 | libsoup | 3.0.4-150400.3.55.1 | SUSE-SU-2026:4616-1 |
| SLES 15 SP5 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLES 15 SP4 | libsoup | 3.0.4-150400.3.55.1 | SUSE-SU-2026:4616-1 |
| SLES 15 SP4 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLES 12 SP5 | libsoup | 2.62.2-5.49.1 | SUSE-SU-2026:4690-1 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | libsoup | 3.6.6-160000.5.1 | SUSE-SU-2026:24470-1 |
| SLES for SAP 15 SP6 | libsoup | 3.4.4-150600.3.59.1 | SUSE-SU-2026:4631-1 |
| SLES for SAP 15 SP6 | libsoup2 | 2.74.3-150600.4.42.1 | SUSE-SU-2026:4703-1 |
| SLES for SAP 15 SP5 | libsoup | 3.0.4-150400.3.55.1 | SUSE-SU-2026:4616-1 |
| SLES for SAP 15 SP5 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLES for SAP 15 SP4 | libsoup | 3.0.4-150400.3.55.1 | SUSE-SU-2026:4616-1 |
| SLES for SAP 15 SP4 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLES 16.0 | libsoup | 3.6.6-160000.5.1 | SUSE-SU-2026:24470-1 |
| SLE Micro 6.0 | libsoup | 3.4.2-159998.1.1 | SUSE-SU-2026:24368-1 |
| SLE Micro 5.5 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLE Micro 5.4 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLE Micro 5.3 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLE HPC 15 SP5 | libsoup | 3.0.4-150400.3.55.1 | SUSE-SU-2026:4616-1 |
| SLE HPC 15 SP5 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
| SLE HPC 15 SP4 | libsoup | 3.0.4-150400.3.55.1 | SUSE-SU-2026:4616-1 |
| SLE HPC 15 SP4 | libsoup2 | 2.74.3-150400.3.43.1 | SUSE-SU-2026:4739-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libsoup | 3.8.1-1.1 | openSUSE-SU-2026:12365-1 |
| openSUSE Tumbleweed | libsoup2 | 2.74.3-25.1 | openSUSE-SU-2026:12132-1 |
| openSUSE Leap 16.0 | libsoup | 3.6.6-160000.5.1 | openSUSE-SU-2026:22181-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libsoup3 +2 | 3.7.2-1.amzn2023 | ALAS2023-2026-3144 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | libsoup | No fix yet | — |
Advisories 12
- SUSE-SU-2026:24470-1 Security update for libsoup SUSE / openSUSE Security Updates · Nov 4, 2026
- openSUSE-SU-2026:22181-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 31, 2026
- openSUSE-SU-2026:12365-1 libsoup-3_0-0-3.8.1-1.1 on GA media SUSE / openSUSE Security Updates · Oct 31, 2026
- WID-SEC-2026-2919 IBM App Connect Enterprise: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 27, 2026
- 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-2026:4690-1 Security update for libsoup SUSE / openSUSE Security Updates · Oct 17, 2026
- SUSE-SU-2026:4703-1 Security update for libsoup2 SUSE / openSUSE Security Updates · Oct 17, 2026
- openSUSE-SU-2026:12132-1 libsoup-2_4-1-2.74.3-25.1 on GA media SUSE / openSUSE Security Updates · Oct 15, 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
- ALAS2023-2026-3144 Important: libsoup3 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Sep 28, 2026