CVE-2019-16751 — devise_token_auth
MEDIUMCVE-2019-16751 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in devise_token_auth. 1 public exploit reference exists, so weaponization risk is real. A fix is available for devise_token_auth — see the affected versions and patch details below.
Devise Token Auth vulnerable to Cross-site Scripting
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2019-16751 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
devise_token_authReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
An issue was discovered in Devise Token Auth through 1.1.2. The omniauth failure endpoint is vulnerable to Reflected Cross Site Scripting (XSS) through the message parameter. Unauthenticated attackers can craft a URL that executes a malicious JavaScript payload in the victim's browser. This affects the fallback_render method in the omniauth callbacks controller.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | devise_token_auth | ≥ 0.1.33&&< 1.1.3 | 1.1.3bundle update devise_token_auth --conservative |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for devise_token_auth, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update devise_token_auth to 1.1.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-16751 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2019-16751 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2019-16751. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2019-16751 in your dependencies?
O3 Security finds CVE-2019-16751 across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.