Python tornado: Prior to 6.6, tornado.web.RedirectHandler URL templates can place regex-capture substitutions where
Affects python-tornadoSource GCVE Database
Not known to be exploited · CVSS 2.1 Low · fixed in 6.6 : update python-tornado when convenient.
Data as of 6 Nov 2026, 23:24 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 2.1 |
|---|
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.6
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 26 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10python-tornadopkg:deb/ubuntu/python-tornado?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSpython-tornadopkg:deb/ubuntu/python-tornado?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSpython-tornadopkg:deb/ubuntu/python-tornado?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu Pro 22.04 LTSpython-tornadopkg:deb/ubuntu/python-tornado?arch=source&distro=esm-apps/jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSpython-tornadopkg:deb/ubuntu/python-tornado?arch=source&distro=esm-apps/focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSpython-tornadopkg:deb/ubuntu/python-tornado?arch=source&distro=esm-apps/bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Tornado to version 6.6 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated in the available data.
Description
A vulnerability in Tornado web framework versions prior to 6.6 allows crafted request paths in tornado.web.RedirectHandler URL templates to manipulate regex-capture substitutions. This can lead to open redirect issues where attackers can control the redirect destination on the application's domain, potentially facilitating phishing attacks. The issue is fixed in version 6.6.
References
- ubuntu.com/security/CVE-2026-116578 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-116578 (opens in a new tab)
- github.com/tornadoweb/tornado/security/advisories/GHSA-pw9p-v7r6-gx4p (opens in a new tab)
- github.com/tornadoweb/tornado/pull/3786 (opens in a new tab)
- github.com/tornadoweb/tornado/commit/940ea725bdd9bc68231d68a105eef17ea6e11233 (opens in a new tab)
- github.com/tornadoweb/tornado/commit/cc75ab0eb3af459c714895a49f682ad354f50117 (opens in a new tab)
- github.com/tornadoweb/tornado/commit/ccb6a2e5482f17997efd4a74b8200d5b4babc035 (opens in a new tab)
- github.com/tornadoweb/tornado/releases/tag/v6.6.0 (opens in a new tab)