USN-8822-1: Libwebsockets vulnerabilities

Publication date

25 September 2026

Overview

Several security issues were fixed in Libwebsockets.


Packages

  • libwebsockets - C library for building WebSocket-based network applications

Details

It was discovered that Libwebsockets incorrectly handled certain SSH
protocol messages in its SSH protocol handler. A remote attacker could
possibly use this issue to cause Libwebsockets to consume excessive
resources, resulting in a denial of service. (CVE-2026-10650)

It was discovered that Libwebsockets incorrectly handled certain malformed
CBOR data. A remote attacker could possibly use this issue to cause
Libwebsockets to crash, resulting in a denial of service, or execute
arbitrary code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04
LTS. (CVE-2026-78161)

It was discovered that Libwebsockets incorrectly handled certain SSH
protocol messages in its SSH protocol handler. A remote attacker could
possibly use this issue to cause Libwebsockets to consume excessive
resources, resulting in a denial of service. (CVE-2026-10650)

It was discovered that Libwebsockets incorrectly handled certain malformed
CBOR data. A remote attacker could possibly use this issue to cause
Libwebsockets to crash, resulting in a denial of service, or execute
arbitrary code. This issue only affected Ubuntu 24.04 LTS and Ubuntu 26.04
LTS. (CVE-2026-78161)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
26.04 LTS resolute libwebsockets-dev –  4.3.5-3ubuntu1.1
libwebsockets-evlib-ev –  4.3.5-3ubuntu1.1
libwebsockets-evlib-glib –  4.3.5-3ubuntu1.1
libwebsockets-evlib-uv –  4.3.5-3ubuntu1.1
libwebsockets-test-server –  4.3.5-3ubuntu1.1
libwebsockets-test-server-common –  4.3.5-3ubuntu1.1
libwebsockets19t64 –  4.3.5-3ubuntu1.1
24.04 LTS noble libwebsockets-dev –  4.3.3-1.1ubuntu0.1~esm2  
libwebsockets-evlib-ev –  4.3.3-1.1ubuntu0.1~esm2  
libwebsockets-evlib-glib –  4.3.3-1.1ubuntu0.1~esm2  
libwebsockets-evlib-uv –  4.3.3-1.1ubuntu0.1~esm2  
libwebsockets-test-server –  4.3.3-1.1ubuntu0.1~esm2  
libwebsockets-test-server-common –  4.3.3-1.1ubuntu0.1~esm2  
libwebsockets19t64 –  4.3.3-1.1ubuntu0.1~esm2  
22.04 LTS jammy libwebsockets-dev –  4.0.20-2ubuntu1.1+esm1  
libwebsockets-test-server –  4.0.20-2ubuntu1.1+esm1  
libwebsockets-test-server-common –  4.0.20-2ubuntu1.1+esm1  
libwebsockets16 –  4.0.20-2ubuntu1.1+esm1  
20.04 LTS focal libwebsockets-dev –  3.2.1-3ubuntu0.1~esm2  
libwebsockets-test-server –  3.2.1-3ubuntu0.1~esm2  
libwebsockets-test-server-common –  3.2.1-3ubuntu0.1~esm2  
libwebsockets15 –  3.2.1-3ubuntu0.1~esm2  

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.


Have additional questions?

Talk to a member of the team ›