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.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| tornadoweb | tornado | affected |
|
No data.
No data.
No data.
Project Subscriptions
No data.
Advisories
| Source | ID | Title |
|---|---|---|
 Github GHSA |
GHSA-cx3h-4qpv-8hc9 | Tornado has out-of-bounds memory access via C extension |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 14 Jul 2026 21:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | Tornado: Out-of-bounds memory access in C extension | |
| Weaknesses | CWE-126 | |
| References |
| |
| Metrics |
cvssV3_1
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-07-14T20:43:03.977Z
Reserved: 2026-06-01T22:03:19.640Z
Link: CVE-2026-49854
Vulnrichment
No data.
NVD
No data.
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses