USN-8625-1: OpenSSL vulnerability

Publication date

30 July 2026

Overview

OpenSSL could be made to crash if it received specially crafted network traffic.


Packages

  • openssl - Secure Socket Layer (SSL) cryptographic library and tools

Details

It was discovered that OpenSSL incorrectly allocated memory buffers in the
SSL/TLS state machine when receiving handshake data. A remote attacker
could possibly use this issue to cause OpenSSL to consume excessive memory,
leading to a denial of service. This issue is known as the "HollowByte"
denial of service.

It was discovered that OpenSSL incorrectly allocated memory buffers in the
SSL/TLS state machine when receiving handshake data. A remote attacker
could possibly use this issue to cause OpenSSL to consume excessive memory,
leading to a denial of service. This issue is known as the "HollowByte"
denial of service.

Update instructions

After a standard system update you need to reboot your computer to 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 libssl3t64 –  3.5.5-1ubuntu3.3
openssl –  3.5.5-1ubuntu3.3
24.04 LTS noble libssl3t64 –  3.0.13-0ubuntu3.12
openssl –  3.0.13-0ubuntu3.12
22.04 LTS jammy libssl3 –  3.0.2-0ubuntu1.26
openssl –  3.0.2-0ubuntu1.26

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