Packages
- python-tornado - scalable, non-blocking web server and tools
Details
USN-8952-2 fixed a regression in Tornado that broke static file serving
for applications that subclass Tornado's StaticFileHandler, such as
Jupyter. Unfortunately, that update's incomplete fix could introduce a regression by rejecting symlinks into system
directories like /usr/share, which distribution packages use for their
JavaScript and fonts, causing web UIs to return 403 errors. 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,
...
USN-8952-2 fixed a regression in Tornado that broke static file serving
for applications that subclass Tornado's StaticFileHandler, such as
Jupyter. Unfortunately, that update's incomplete fix could introduce a regression by rejecting symlinks into system
directories like /usr/share, which distribution packages use for their
JavaScript and fonts, causing web UIs to return 403 errors. 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 – 6.5.5-5ubuntu1.3 | ||
| 26.04 LTS resolute | python3-tornado – 6.5.4-0.1ubuntu0.4 | ||
| 24.04 LTS noble | python3-tornado – 6.4.0-1ubuntu0.8 | ||
| 22.04 LTS jammy | python3-tornado – 6.1.0-3ubuntu0.1~esm8 | ||
| 20.04 LTS focal | python3-tornado – 6.0.3+really5.1.1-3ubuntu0.1~esm9 | ||
| 18.04 LTS bionic | python3-tornado – 4.5.3-1ubuntu0.2+esm6 | ||
| 16.04 LTS xenial | python3-tornado – 4.2.1-1ubuntu3.1+esm6 | ||
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