Information disclosure in Tornadoweb Tornado

CVE-2026-91992

Tornado before 6.5.7 contains a credential leak vulnerability in CurlAsyncHTTPClient where pycurl handles are reused across requests without proper state clearing. Attackers can obtain sensitive credentials by issuing requests through the same client instance, allowing TLS certificates or proxy authentication to persist across unintended requests.

Vulnerability class: Information Disclosure

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-91992?
CVE-2026-91992 is a medium-severity vulnerability in Tornadoweb Tornado, classified under Information Disclosure. CVSS score: 5.9/10. Published 2026-09-15.
How severe is CVE-2026-91992?
Medium severity. CVSS v3 base score is 5.9 out of 10.