CVE-2026-15709
Fixed in a distro release EPSS <1%CVSS 7.5
A flaw was found in libsoup's WebSocket implementation when using the permessage-deflate extension. The extension's decompression loop (inflate()) processes data in chunks without enforcing an upper boundary limit on the output buffer size. While libsoup limits the incoming compressed frame size via max_incoming_payload_size, it fails to track or limit memory allocation during decompression. A separate check for decompressed size (max_total_message_size) exists but executes only after inflation is complete, and it is entirely disabled by default for client connections. A remote, unauthenticated attacker can exploit this by sending a small, highly compressed payload (a decompression bomb), causing unbounded memory allocation that triggers an Out-of-Memory (OOM) crash and a Denial of Service (DoS).
Products: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On, Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On, Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.6 Extended Update Support, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | libsoup3 | 3.6.5-3.el10_2.14 |
| AlmaLinux 10 | libsoup3-devel | 3.6.5-3.el10_2.14 |
| AlmaLinux 10 | libsoup3-doc | 3.6.5-3.el10_2.14 |
| AlmaLinux 9 | libsoup | 2.72.0-16.el9_8.3 |
| AlmaLinux 9 | libsoup-devel | 2.72.0-16.el9_8.3 |
| Amazon Linux 2023 | libsoup | 2.72.0-6.amzn2023.0.14 |
| Amazon Linux 2023 | libsoup-devel | 2.72.0-6.amzn2023.0.14 |
| Amazon Linux 2023 | libsoup-doc | 2.72.0-6.amzn2023.0.14 |
| Amazon Linux 2023 | libsoup3 | 3.6.6-60.amzn2023 |
| Amazon Linux 2023 | libsoup3-devel | 3.6.6-60.amzn2023 |
| Amazon Linux 2023 | libsoup3-doc | 3.6.6-60.amzn2023 |
| Debian 12 | libsoup2.4 | no fix |
| Debian 12 | libsoup3 | no fix |
| Debian 13 | libsoup2.4 | no fix |
| Debian 13 | libsoup3 | no fix |
| Debian 14 | libsoup3 | 3.8.0-1 |
| Red Hat Enterprise Linux 10.2 | libsoup3 | 0:3.6.5-3.el10_2.14 |
| Red Hat Enterprise Linux 10.2 | libsoup3-debuginfo | 0:3.6.5-3.el10_2.14 |
| Red Hat Enterprise Linux 10.2 | libsoup3-debugsource | 0:3.6.5-3.el10_2.14 |
| Red Hat Enterprise Linux 10.2 | libsoup3-devel | 0:3.6.5-3.el10_2.14 |
| Red Hat Enterprise Linux 10.2 | libsoup3-doc | 0:3.6.5-3.el10_2.14 |
| Red Hat Enterprise Linux 9 | libsoup | 0:2.72.0-16.el9_8.3 |
| Red Hat Enterprise Linux 9 | libsoup-debuginfo | 0:2.72.0-16.el9_8.3 |
| Red Hat Enterprise Linux 9 | libsoup-debugsource | 0:2.72.0-16.el9_8.3 |
| Red Hat Enterprise Linux 9 | libsoup-devel | 0:2.72.0-16.el9_8.3 |
| Red Hat Enterprise Linux eus 10.0 | libsoup3 | 0:3.6.5-3.el10_0.17 |
| Red Hat Enterprise Linux eus 10.0 | libsoup3-debuginfo | 0:3.6.5-3.el10_0.17 |
| Red Hat Enterprise Linux eus 10.0 | libsoup3-debugsource | 0:3.6.5-3.el10_0.17 |
| Red Hat Enterprise Linux eus 10.0 | libsoup3-devel | 0:3.6.5-3.el10_0.17 |
| Red Hat Enterprise Linux eus 10.0 | libsoup3-doc | 0:3.6.5-3.el10_0.17 |
| Red Hat rhel aus 8.4 | libsoup | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel aus 8.4 | libsoup-debuginfo | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel aus 8.4 | libsoup-debugsource | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel aus 8.4 | libsoup-devel | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel aus 8.6 | libsoup | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel aus 8.6 | libsoup-debuginfo | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel aus 8.6 | libsoup-debugsource | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel aus 8.6 | libsoup-devel | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel e4s 8.8 | libsoup | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel e4s 8.8 | libsoup-debuginfo | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel e4s 8.8 | libsoup-debugsource | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel e4s 8.8 | libsoup-devel | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel e4s 9.2 | libsoup | 0:2.72.0-8.el9_2.13 |
| Red Hat rhel e4s 9.2 | libsoup-debuginfo | 0:2.72.0-8.el9_2.13 |
| Red Hat rhel e4s 9.2 | libsoup-debugsource | 0:2.72.0-8.el9_2.13 |
| Red Hat rhel e4s 9.2 | libsoup-devel | 0:2.72.0-8.el9_2.13 |
| Red Hat rhel e4s 9.4 | libsoup | 0:2.72.0-8.el9_4.12 |
| Red Hat rhel e4s 9.4 | libsoup-debuginfo | 0:2.72.0-8.el9_4.12 |
| Red Hat rhel e4s 9.4 | libsoup-debugsource | 0:2.72.0-8.el9_4.12 |
| Red Hat rhel e4s 9.4 | libsoup-devel | 0:2.72.0-8.el9_4.12 |
| Red Hat rhel eus 9.6 | libsoup | 0:2.72.0-10.el9_6.9 |
| Red Hat rhel eus 9.6 | libsoup-debuginfo | 0:2.72.0-10.el9_6.9 |
| Red Hat rhel eus 9.6 | libsoup-debugsource | 0:2.72.0-10.el9_6.9 |
| Red Hat rhel eus 9.6 | libsoup-devel | 0:2.72.0-10.el9_6.9 |
| Red Hat rhel eus long life 8.4 | libsoup | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel eus long life 8.4 | libsoup-debuginfo | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel eus long life 8.4 | libsoup-debugsource | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel eus long life 8.4 | libsoup-devel | 0:2.62.3-2.el8_4.10 |
| Red Hat rhel eus long life 8.6 | libsoup | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel eus long life 8.6 | libsoup-debuginfo | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel eus long life 8.6 | libsoup-debugsource | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel eus long life 8.6 | libsoup-devel | 0:2.62.3-2.el8_6.10 |
| Red Hat rhel tus 8.8 | libsoup | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel tus 8.8 | libsoup-debuginfo | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel tus 8.8 | libsoup-debugsource | 0:2.62.3-3.el8_8.11 |
| Red Hat rhel tus 8.8 | libsoup-devel | 0:2.62.3-3.el8_8.11 |
| Rocky Linux 9 | libsoup | 0:2.72.0-16.el9_8.3 |
| Ubuntu 22.04 LTS | libsoup2.4 | no fix |
| Ubuntu 24.04 LTS | libsoup2.4 | no fix |
| Ubuntu 24.04 LTS | libsoup3 | no fix |
| Ubuntu 26.04 LTS | libsoup3 | no fix |
| Ubuntu 26.10 | libsoup2.4 | no fix |
| Ubuntu 26.10 | libsoup3 | no fix |
| Ubuntu Pro 16.04 LTS | libsoup2.4 | no fix |
| Ubuntu Pro 18.04 LTS | libsoup2.4 | no fix |
| Ubuntu Pro 20.04 LTS | libsoup2.4 | no fix |
| Ubuntu Pro 22.04 LTS | libsoup3 | no fix |
| Ubuntu Pro 26.04 LTS | libsoup2.4 | no fix |