USN-8861-1: OpenSSL vulnerabilities
Publication date
1 October 2026
Overview
Several security issues were fixed in OpenSSL.
Releases
Packages
- openssl - Secure Socket Layer (SSL) cryptographic library and tools
Details
It was discovered that OpenSSL had an inefficient algorithm in its QUIC
stream reassembly implementation. A remote attacker could possibly use this
issue to cause OpenSSL to use excessive CPU resources, leading to a denial
of service. (CVE-2026-42772)
It was discovered that OpenSSL did not properly limit memory allocated for
QUIC packet buffers. A remote attacker could possibly use this issue to
cause OpenSSL to use excessive memory resources, leading to a denial of
service. (CVE-2026-54873)
It was discovered that OpenSSL had an inefficient algorithm in its QUIC
stream reassembly implementation. A remote attacker could possibly use this
issue to cause OpenSSL to use excessive CPU resources, leading to a denial
of service. (CVE-2026-42772)
It was discovered that OpenSSL did not properly limit memory allocated for
QUIC packet buffers. A remote attacker could possibly use this issue to
cause OpenSSL to use excessive memory resources, leading to a denial of
service. (CVE-2026-54873)
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 – 3.5.5-1ubuntu3.7 | ||
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