> USN-8952-3: Tornado regression

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)