CVE-2026-126347: Tornado: Open redirect via triple-slash redirect paths
Noroxi assessment
Priority: Monitor (action score 12/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Anyone who can reach it over the internet can trigger it. No account or password is required. A user must open a link or visit a page. Special conditions such as timing or configuration are required.
- Fixed version: tornadoweb tornado 6.6.1.
Low priority for now. Upgrade to tornadoweb tornado 6.6.1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
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.
- Published
- Nov 12, 2026
- Updated
- Nov 12, 2026
- EPSS
- —
- CWE
- CWE-601
Report tools
Action score
12
Low priority for now.
- CVSS
- 12 / 40 · 3.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · —
CNA vs NVD score
- NVD
- —
- CNA · GitHub_M
- 3.1
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
tornadoweb tornado
- < 6.6.1affected
Same product
tornadoweb: all recordsOther highest-scoring records for the same primary product.
- CVE-2024-14029Tornado before 6.4.1 HTTP Request Smuggling via Transfer-Encoding36Monitor
- CVE-2023-54397Tornado before 6.3.3 HTTP Request Smuggling via Content-Length36Monitor
- CVE-2026-103262Tornado before 6.5.9 Denial of Service via CurlAsyncHTTPClient34Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-116578Oct 26, 2026 · Tornado: Open redirect in RedirectHandler via protocol-relative URLs8Monitor
- ← EarlierCVE-2026-123534Nov 8, 2026 · Tornado before 6.6 Path Traversal via static_url() Version Hashing33Monitor
- ← EarlierCVE-2026-123535Nov 8, 2026 · Tornado before 6.6 Cookie Attribute Injection via set_cookie max_age9Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| tornadoweb tornado | 6.6.1 · description | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 13, 2026same day
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-11657817 days apartTornado: Open redirect in RedirectHandler via protocol-relative URLs8Monitor
Not on record for this CVE: EPSS history · researcher credit · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- A user must open a link or visit a page.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- none
- Integrity
- low · data or configuration can be modified
- Availability
- none
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- Low
- Availability impact
- None
Weakness class (CWE)
CWE-601 · URL Redirection to Untrusted Site ('Open Redirect')CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log (2)
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.