This page tracks the Debian fix status. The vulnerability itself is described on the main CVE page.
View CVE-2026-49855 →
DEBIAN-CVE-2026-49855
Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, Tornado gzip decompression routines processed limited-size chun...
Original description
The description as published by the source.
Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, Tornado gzip decompression routines processed limited-size chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an HTTPServer configured with decompress_request=True to consume effectively unlimited memory. This issue is fixed in version 6.5.6.
Source: OSV.dev (Open Source Vulnerabilities) OSV
Affected packages
Debian:12
python-tornado
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Debian:13
python-tornado
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Debian:14
python-tornado
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
References
- advisory security-tracker.debian.org