CVE-2025-57816 — ethyca-fides
Fix: ethyca/fides@59903c1CVE-2025-57816 is a CWE-799 vulnerability in ethyca-fides. A fix is available for ethyca-fides — see the affected versions and patch details below.
Fides Webserver API Rate Limiting Vulnerability in Proxied Environments
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-2025-57816.
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
ethyca-fidesReal-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
Summary
The Fides Webserver API's built-in IP-based rate limiting is ineffective in environments with CDNs, proxies or load balancers. The system incorrectly applies rate limits based on directly connected infrastructure IPs rather than client IPs, and stores counters in-memory rather than in a shared store. This allows attackers to bypass intended rate limits and potentially cause denial of service.
This vulnerability only affects deployments relying on Fides's built-in rate limiting for protection. Deployments using external rate limiting solutions (WAFs, API gateways, etc.) are not affected.
Details
The vulnerability has two components:
- Rate limiting uses the immediate connection source IP instead of the actual client IP
- Rate limit counters are maintained in-memory per container rather than in a shared store
In production environments, these issues allow clients to exceed intended rate limits and enable attackers to trigger rate limits on infrastructure IPs, causing legitimate clients to receive 429 responses.
Impact
This vulnerability affects availability, allowing attackers to:
- Bypass rate limits, potentially leading to resource exhaustion
- Cause a denial of service for legitimate clients by deliberately triggering rate limits on infrastructure IPs
Patches
The vulnerability has been patched in Fides version 2.69.1. Users are advised to upgrade to this version or later to secure their systems against this threat.
Workarounds
There are no application-level workarounds. However, rate limiting may instead be implemented externally at the infrastructure level using a WAF, API Gateway, or similar technology.
Risk Level
This vulnerability has been assigned a severity of MEDIUM.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | ethyca-fides | all versions | 2.69.1pip install --upgrade 'ethyca-fides==2.69.1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ethyca-fides, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ethyca-fides to 2.69.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-57816 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-2025-57816 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-57816. 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-2025-57816 in your dependencies?
O3 Security finds CVE-2025-57816 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.