CVE-2026-91992

Status: DeferredHigh (8.2)—

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.

CVSS

Version: 4.0
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Base score: 8.2

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.26%
Percentile among all scored CVEs: 16
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1552.007 Container APIcredential access90 %
Secondary impactT1005 Data from Local Systemcollection75 %

Vulnerabilidad en Tornado/pycurl accesible por red (AV:N) sin privilegios (PR:N) que permite obtener credenciales (TLS, proxy) reutilizando handles. CWE-200 (exposición de información).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account Management Network Segmentation Limit Access to Resource Over Network Vulnerability Scanning User Account Management Filter Network Traffic

Affected technologies (2)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Pycurl — Pycurl^AI Tornado — Tornado^AI

CWEs

CWE-200

References

Raw JSON (NVD)

Show

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    }
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