CVE-2023-28370 is a medium-severity (CVSS 6.1) Open Redirect vulnerability in tornado. A fix is available for tornado — see the affected versions and patch details below.
Open redirect in Tornado
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-28370.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
tornadoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | tornado | all versions | 6.3.2pip install --upgrade 'tornado==6.3.2' |
Affected Products
tornadotornadowebDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tornado, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update tornado to 6.3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-28370 is resolved across your whole dependency graph.
Workarounds
Stop reflecting attacker-controlled destinations: resolve every redirect target against an allowlist of paths or hosts you own, prefer a server-side key over a full URL in the request, and reject absolute URLs entirely where the flow only ever needs a relative one.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.Source: Red Hat security advisory for CVE-2023-28370 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 9 | python-tornado-0:6.1.0-9.el9 | RHSA-2023:6523 |
Frequently Asked Questions
Is CVE-2023-28370 in your dependencies?
Find it across PyPI, including transitive dependencies.