CVE-2026-49854
Tornado: Out-of-bounds memory access in C extension
- State
- Published
- Severity
- 5.3 Medium
- Published
- Jul 14, 2026
- Updated
- Jul 15, 2026
- Reserved
- Jun 1, 2026
Description
Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, the optional native extension tornado.speedups implemented websocket_mask without validating that the mask argument is exactly four bytes, allowing the C function to read up to three bytes beyond the provided buffer when reached through Tornado XSRF token decoding with the native extension active. This issue is fixed in version 6.5.6.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.3 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N | GitHub_M |
Weaknesses
- CWE-126 Buffer Over-read
Affected Products
| Product | Versions |
|---|---|
tornadotornadoweb |
|
References
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