Fides Webserver API Rate Limiting Vulnerability in Proxied Environments

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

6.3 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2025-57816: 0.43% estimated exploitation activity in the next 30 days; percentile 37.85 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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: 1. Rate limiting uses the immediate connection source IP instead of the actual client IP 2. 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…

Published by the source

8 Sep 2025, 20:45 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 13:35 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-fq34-xw6c-fphf

2. Revision 2 · amended · 24 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-fq34-xw6c-fphf

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2025-57816

Advisory: Fides Webserver API Rate Limiting Vulnerability in Proxied Environments
IDs: CVE-2025-57816, GHSA-fq34-xw6c-fphf
Record: https://patchnext.com/advisories/cve-2025-57816 (revision 3, source checked 26 Oct 2026, 13:35 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: ethyca-fides 2.69.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI ethyca-fides: affected < 2.69.1; fixed in 2.69.1

## Suggested inspection (read-only)
- `python -m pip show ethyca-fides`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on ethyca-fides.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-fq34-xw6c-fphf (OSV record GHSA-fq34-xw6c-fphf lists affected ranges: PyPI ethyca-fides >=0 <2.69.1 (fixed))
- Verified: https://github.com/advisories/GHSA-fq34-xw6c-fphf (GitHub-reviewed advisory GHSA-fq34-xw6c-fphf lists affected ranges: PyPI ethyca-fides >=0 <2.69.1)

Commands are suggestions: review each one before running it.