VULNERABILITY INTELLIGENCE

CVE-2026-49855

CVSS score7.5 HIGH
EPSS probability0.57%
CISA KEVNot currently listed
Published2026-07-14
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

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.

Weakness classification

  • security-advisories@github.com: CWE-409

Primary references