Back Linuxsecurity Ubuntu 25.10: Tornado Critical XSS DoS Flaws USN-7950-1 CVE-2025
A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 25.10 - Ubuntu 25.04 - 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 special characters in HTTP headers. An attacker could possibly use this issue to execute a cross- site scripting (XSS) attack. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.04, and Ubuntu 25.10. (CVE-2025-67724) It was discovered that Tornado incorrectly handled repeated HTTP headers. An attacker could possibly use this issue to cause Tornado to use excessive resources, causing a denial of service. (CVE-2025-67725) It was discovered that Tornado incorrectly handled parsing of certain HTTP
A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 25.10 - Ubuntu 25.04 - 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 special characters in HTTP headers. An attacker could possibly use this issue to execute a cross- site scripting (XSS) attack. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.04, and Ubuntu 25.10. (CVE-2025-67724) It was discovered that Tornado incorrectly handled repeated HTTP headers. An attacker could possibly use this issue to cause Tornado to use excessive resources, causing a denial of service. (CVE-2025-67725) It was discovered that Tornado incorrectly handled parsing of certain HTTP
The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 python3-tornado 6.4.2-3ubuntu0.2 Ubuntu 25.04 python3-tornado 6.4.2-1ubuntu0.25.04.3 Ubuntu 24.04 LTS python3-tornado 6.4.0-1ubuntu0.4 Ubuntu 22.04 LTS python3-tornado 6.1.0-3ubuntu0.1~esm4 Available with Ubuntu Pro Ubuntu 20.04 LTS python3-tornado 6.0.3+really5.1.1-3ubuntu0.1~esm3 Available with Ubuntu Pro Ubuntu 18.04 LTS python-tornado 4.5.3-1ubuntu0.2+esm2 Available with Ubuntu Pro python3-tornado 4.5.3-1ubuntu0.2+esm2 Available with Ubuntu Pro Ubuntu 16.04 LTS python-tornado 4.2.1-1ubuntu3.1+esm2 Available with Ubuntu Pro python3-tornado 4.2.1-1ubuntu3.1+esm2 Available with Ubuntu Pro In general, a standard system update will make all the necessary changes.
The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 python3-tornado 6.4.2-3ubuntu0.2 Ubuntu 25.04 python3-tornado 6.4.2-1ubuntu0.25.04.3 Ubuntu 24.04 LTS python3-tornado 6.4.0-1ubuntu0.4 Ubuntu 22.04 LTS python3-tornado 6.1.0-3ubuntu0.1~esm4 Available with Ubuntu Pro Ubuntu 20.04 LTS python3-tornado 6.0.3+really5.1.1-3ubuntu0.1~esm3 Available with Ubuntu Pro Ubuntu 18.04 LTS python-tornado 4.5.3-1ubuntu0.2+esm2 Available with Ubuntu Pro python3-tornado 4.5.3-1ubuntu0.2+esm2 Available with Ubuntu Pro Ubuntu 16.04 LTS python-tornado 4.2.1-1ubuntu3.1+esm2 Available with Ubuntu Pro python3-tornado 4.2.1-1ubuntu3.1+esm2 Available with Ubuntu Pro In general, a standard system update will make all the necessary changes.
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