CVE-2026-49854NVD

Vulnerability Summary

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.

Severity Level

MEDIUM(5.3)

Published Date

Jul 14, 2026

Last Modified

Jul 15, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.34%Probability

Root Weakness (CWE)

CWE-126: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 5.3 (MEDIUM)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityLow

IntegrityNone

AvailabilityNone

Affected & Patched Versions

Affected Versions

Not provided by NVD for this CVE.

Patched Versions

Not provided by NVD for this CVE.

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