Packages
- python-tornado - scalable, non-blocking web server and tools
Details
USN-8952-1 fixed vulnerabilities in Tornado. Unfortunately that update was incomplete due
to an incomplete fix for CVE-2026-103263, which broke static file
serving for applications that subclass Tornado's StaticFileHandler,
such as Jupyter, and could introduce a regression. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that Tornado did not properly handle certain HTTP requests
and network inputs. An attacker could possibly use these issues to cause a
denial of service, expose sensitive information, or bypass access controls.
(CVE-2023-54397, CVE-2024-14029, CVE-2026-91990, CVE-2026-91992,
CVE-2026-103262,
USN-8952-1 fixed vulnerabilities in Tornado. Unfortunately that update was incomplete due
to an incomplete fix for CVE-2026-103263, which broke static file
serving for applications that subclass Tornado's StaticFileHandler,
such as Jupyter, and could introduce a regression. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that Tornado did not properly handle certain HTTP requests
and network inputs. An attacker could possibly use these issues to cause a
denial of service, expose sensitive information, or bypass access controls.
(CVE-2023-54397, CVE-2024-14029, CVE-2026-91990, CVE-2026-91992,
CVE-2026-103262, CVE-2026-103263)
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 | ||
|---|---|---|---|
| 26.10 stonking | python3-tornado – 6.5.5-5ubuntu1.2 | ||
| 26.04 LTS resolute | python3-tornado – 6.5.4-0.1ubuntu0.3 | ||
| 24.04 LTS noble | python3-tornado – 6.4.0-1ubuntu0.7 | ||
| 22.04 LTS jammy | python3-tornado – 6.1.0-3ubuntu0.1~esm7 | ||
| 20.04 LTS focal | python3-tornado – 6.0.3+really5.1.1-3ubuntu0.1~esm8 | ||
| 18.04 LTS bionic | python3-tornado – 4.5.3-1ubuntu0.2+esm5 | ||
| 16.04 LTS xenial | python3-tornado – 4.2.1-1ubuntu3.1+esm5 | ||
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