CVE-2026-116578 json
Tornado: Open redirect in RedirectHandler via protocol-relative URLs
published 2026-10-26 13 d ago modified 2026-10-30 9 d ago also GHSA-pw9p-v7r6-gx4p , EUVD-2026-110319
- cvss
- 2.1
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 40%
- public exploits
- 0
- none known
Summary
Tornado is a Python web framework and asynchronous networking library. Prior to 6.6, tornado.web.RedirectHandler URL templates can place regex-capture substitutions where crafted request paths change the redirect scheme or network location. Affected placements include substitutions at the start of a path, directly after a fixed host, or at the beginning of the template, including protocol-relative, absolute, backslash, encoded, host-extension, and user-info variants interpreted by browsers as attacker-controlled destinations. Static templates and substitutions after a fixed host followed by a slash are not affected. An attacker can use the resulting open redirect on the application's domain for phishing. This issue is fixed in version 6.6.
Patch / fix
- pypi tornado 6.6
- python-tornado6 openSUSE Tumbleweed 6.6-1.1
opensuse advisories openSUSE-SU-2026:12440-1
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-116578 updated cvss 6.1
tornado: tornado: Open redirect via crafted request paths in RedirectHandler URL templates
-
Red Hat Lightspeed Core lightspeed-core/rag-tool-cpu-rhel9, lightspeed-core/lightspeed-stack-rhel9, lightspeed-core/rag-tool-cuda-12.9-rhel9 Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-ocp-rag-rhel9 Red Hat Ansible Automation Platform 2 ansible-automation-platform-26/lightspeed-chatbot-rhel9, ansible-automation-platform-27/lightspeed-chatbot-rhel9 Red Hat Enterprise Linux 8 pcs, pcs-snmp Red Hat Enterprise Linux 9 python3-tornado, python-tornado 6.5.8-0.el10_0.1 Red Hat Enterprise Linux 10 python-tornado 6.5.8-0.el10_0.1affected: workaround, no fix available “Upgrade tornado to 6.6. Avoid regex-capture substitutions in the scheme/netloc or start-of-path placement of RedirectHandler url templates; tornado 6.6 rejects such requests with HTTP 400.”
+4 more productsfewer
Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-gaudi-rhel9, rhelai3/disk-image-cuda-rhel9 Red Hat OpenShift AI (RHOAI) rhoai/odh-feature-server-rhel9, rhoai/odh-llama-stack-core-rhel9, rhoai/odh-th-torch-cpu-py312-rhel9, rhoai/odh-th-torch-cuda-py312-rhel9, rhoai/odh-th-torch-rocm-py312-rhel9, rhoai/odh-th06-cpu-torch210-py312-rhel9, +23 more Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9, python-flit 3.9.0-3.1.el9ocp, python-pep517 0.13.0-5.2.el9ocp, python-tornado 6.5.8-0.el10_0.1 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9 -
Red Hat OpenStack Platform 16.2 rhosp-rhel8/openstack-redis, rhosp-rhel8/openstack-haproxy, rhosp-rhel8/openstack-mariadb, rhosp-rhel8/openstack-rabbitmq, rhosp-rhel8/openstack-ovn-northd, rhosp-rhel8/openstack-manila-share, +2 moreaffected: workaround, no fix planned “Upgrade tornado to 6.6. Avoid regex-capture substitutions in the scheme/netloc or start-of-path placement of RedirectHandler url templates; tornado 6.6 rejects such requests with HTTP 400.”
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 9 d ago
Exploit prediction
0.46% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 2.1 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N |
| CNA | 4.0 | 2.1 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/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 |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | tornado | <6.6 |
6.6 |
Affected products
- tornadoweb tornado
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
github.com
/tornadoweb/tornado/pull/3786
web
-
github.com
/tornadoweb/tornado/commit/940ea725bdd9bc68231d68a105eef17ea6e11233
web
-
github.com
/tornadoweb/tornado/commit/cc75ab0eb3af459c714895a49f682ad354f50117
web
-
github.com
/tornadoweb/tornado/commit/ccb6a2e5482f17997efd4a74b8200d5b4babc035
web
-
github.com
/tornadoweb/tornado/security/advisories/GHSA-pw9p-v7r6-gx4p
web
-
github.com
/tornadoweb/tornado/releases/tag/v6.6.0
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-116578
advisory
-
github.com
/tornadoweb/tornado
package
Sources
- CVE List CVE-2026-116578
- GitHub Advisory GHSA-pw9p-v7r6-gx4p
- NVD CVE-2026-116578
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