ALAS2023-2026-2160


Amazon Linux 2023 Security Advisory: ALAS2023-2026-2160
Advisory Released Date: 2026-09-14
Advisory Updated Date: 2026-09-14
Severity: Important

Issue Overview:

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). (CVE-2026-15709)


Affected Packages:

libsoup


Issue Correction:
Run dnf update libsoup --releasever 2023.12.20260914 or dnf update --advisory ALAS2023-2026-2160 --releasever 2023.12.20260914 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation

New Packages:
aarch64:
    libsoup-debuginfo-2.72.0-6.amzn2023.0.14.aarch64
    libsoup-debugsource-2.72.0-6.amzn2023.0.14.aarch64
    libsoup-devel-2.72.0-6.amzn2023.0.14.aarch64
    libsoup-2.72.0-6.amzn2023.0.14.aarch64

noarch:
    libsoup-doc-2.72.0-6.amzn2023.0.14.noarch

src:
    libsoup-2.72.0-6.amzn2023.0.14.src

x86_64:
    libsoup-debuginfo-2.72.0-6.amzn2023.0.14.x86_64
    libsoup-debugsource-2.72.0-6.amzn2023.0.14.x86_64
    libsoup-devel-2.72.0-6.amzn2023.0.14.x86_64
    libsoup-2.72.0-6.amzn2023.0.14.x86_64