CVSS 3.1
3.1 lowCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:NCVE-2026-126347
Tornado: Open redirect via triple-slash redirect paths
Low (3.1) in tornadoweb tornado.
On this page
Tornado is a Python web framework and asynchronous networking library. In versions through 6.6.0, applications using tornado.web.RedirectHandler with URL templates that allow attacker-controlled substitutions to influence the destination can be vulnerable to an open redirect using three or more leading slashes. Differences between Python’s URL parsing and browser URL interpretation allow a crafted destination to redirect a user to an attacker-controlled host. The remediation for CVE-2026-116578 in version 6.6.0 did not fully address this case. This issue is fixed in version 6.6.1.
Severity
- CWE
- CWE-601 URL Redirection to Untrusted Site (Open Redirect)
- OWASP Top 10
- A01:2025 Broken Access Control
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
Ask an AI about this CVE
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Explain CVE-2026-126347 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-126347?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-126347?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-126347 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| tornadoweb tornado | < 6.6.1 |
Attack patterns (CAPEC)
- CAPEC-178 Cross-Site Flashing Likelihood: Medium · Severity: Medium
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.