Tornado: Quadratic DoS via Crafted Multipart Parameters

Summary The parseparam function in Tornado's httputil.py is used to parse specific HTTP header values, such as those in multipart/form-data. This function uses an inefficient algorithm that repeatedly calls string.count within a nested loop while processing quoted semicolons e.g., param=";". As a...

Tornado: Quadratic DoS via Repeated Header Coalescing

Summary The HTTPHeaders.add method in Tornado accumulates values using string concatenation when the same header name is repeated. Due to Python string immutability, each concatenation copies the entire string, resulting in On² time complexity. Given Tornado's single event loop architecture, a...

EUVD-2025-203031

Tornado: Quadratic DoS via Repeated Header Coalescing...

EUVD-2025-203032

Tornado vulnerable to Header Injection and XSS via reason argument...

Linux Distros Unpatched Vulnerability : CVE-2026-49853

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only...

CVE-2026-49853

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, authusername, authpassword, and authmode in place when a redirect changed scheme, host, or port...

DEBIAN-CVE-2026-49853

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, authusername, authpassword, and authmode in place when a redirect changed scheme, host, or port...

CVE-2026-49854

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, the optional native extension tornado.speedups implemented websocketmask without validating that the mask argument is exactly four bytes, allowing the C function to read up to three bytes beyond the provided...

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 chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an...

DEBIAN-CVE-2026-49854

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, the optional native extension tornado.speedups implemented websocketmask without validating that the mask argument is exactly four bytes, allowing the C function to read up to three bytes beyond the provided...

CVE-2026-49853

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, authusername, authpassword, and authmode in place when a redirect changed scheme, host, or port...

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 chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an...

UBUNTU-CVE-2026-49854

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, the optional native extension tornado.speedups implemented websocketmask without validating that the mask argument is exactly four bytes, allowing the C function to read up to three bytes beyond the provided...

UBUNTU-CVE-2026-49853

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, SimpleAsyncHTTPClient shallow-copied redirected requests and removed only the Host header, leaving Authorization, authusername, authpassword, and authmode in place when a redirect changed scheme, host, or port...

UBUNTU-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 chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an...

CVE-2026-49855

Tornado (Python) prior to 6.5.6 allows a malicious server accessed via SimpleAsyncHTTPClient or an HTTPServer with decompress_request=True to accumulate decompressed data without an overall size limit, potentially causing memory exhaustion. Affected is gzip decompression routines that previously ...

CVE-2026-49855 tornado AsyncHTTPClient accumulates decompressed chunks without size limit (gzip bomb)

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...

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 chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an...

CVE-2026-49854

Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, the optional native extension tornado.speedups implemented websocketmask without validating that the mask argument is exactly four bytes, allowing the C function to read up to three bytes beyond the provided...

CVE-2026-49854

Summary: Tornado’s optional native extension tornado.speedups mishandles the websocket_mask length, reading beyond a four-byte buffer when invoked through the XSRF token decoder with the extension active. This out-of-bounds access affects Tornado up to version 6.5.5 and is fixed in 6.5.6. Impact:...