CVE-2025-66453 — rhino
CVE-2025-66453 is a Uncontrolled Resource Consumption vulnerability in org.mozilla:rhino. A fix is available for org.mozilla:rhino — see the affected versions and patch details below.
Rhino vulnerable high CPU usage and potential DoS when passing specific numbers to toFixed() function
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2025-66453.
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.
Real-World Exposure
org.mozilla:rhino☕org.mozilla:rhino☕org.mozilla:rhinoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Rhino is an open-source implementation of JavaScript written entirely in Java. Prior to 1.8.1, 1.7.15.1, and 1.7.14.1, when an application passed an attacker controlled float poing number into the toFixed() function, it might lead to high CPU consumption and a potential Denial of Service. Small numbers go through this call stack: NativeNumber.numTo > DToA.JS_dtostr > DToA.JS_dtoa > DToA.pow5mult where pow5mult attempts to raise 5 to a ridiculous power. This vulnerability is fixed in 1.8.1, 1.7.15.1, and 1.7.14.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.mozilla:rhino | all versions | 1.7.14.1org.mozilla:rhino:1.7.14.1 |
| ☕Maven | org.mozilla:rhino | ≥ 1.7.15&&< 1.7.15.1 | 1.7.15.1org.mozilla:rhino:1.7.15.1 |
| ☕Maven | org.mozilla:rhino | ≥ 1.8.0&&< 1.8.1 | 1.8.1org.mozilla:rhino:1.8.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.mozilla:rhino, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.mozilla:rhino to 1.7.14.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-66453 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-2025-66453 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-66453. 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-2025-66453 in your dependencies?
O3 Security finds CVE-2025-66453 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.