[USN-8198-1] Tornado vulnerabilities

========================================================================== Ubuntu Security Notice USN-8198-1 April 22, 2026 python-tornado vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 25.10 - Ubuntu 24.04 LTS - Ubuntu 22.04 LTS - Ubuntu 20.04 LTS - Ubuntu 18.04 LTS - Ubuntu 16.04 LTS Summary: Several security issues were fixed in Tornado. Software Description: - python-tornado: scalable, non-blocking web server and tools Details: It was discovered that Tornado incorrectly handled parsing of large multipart request bodies. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-31958) It was discovered that Tornado did not properly validate characters in cookie values. An attacker could possibly use this issue to inject arbitrary cookie attributes. (CVE-2026-35536) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 python3-tornado 6.4.2-3ubuntu0.3 Ubuntu 24.04 LTS python3-tornado 6.4.0-1ubuntu0.5 Ubuntu 22.04 LTS python3-tornado 6.1.0-3ubuntu0.1~esm5 Available with Ubuntu Pro Ubuntu 20.04 LTS python3-tornado 6.0.3+really5.1.1-3ubuntu0.1~esm5 Available with Ubuntu Pro Ubuntu 18.04 LTS python-tornado 4.5.3-1ubuntu0.2+esm3 Available with Ubuntu Pro python3-tornado 4.5.3-1ubuntu0.2+esm3 Available with Ubuntu Pro Ubuntu 16.04 LTS python-tornado 4.2.1-1ubuntu3.1+esm3 Available with Ubuntu Pro python3-tornado 4.2.1-1ubuntu3.1+esm3 Available with Ubuntu Pro In general, a standard system update will make all the necessary changes. References: https://ubuntu.com/security/notices/USN-8198-1 CVE-2026-31958, CVE-2026-35536 Package Information: https://launchpad.net/ubuntu/+source/python-tornado/6.4.2-3ubuntu0.3 https://launchpad.net/ubuntu/+source/python-tornado/6.4.0-1ubuntu0.5