CVE-2026-0650 — flagr
Fix: openflagr/flagr@fe83dc8CVE-2026-0650 is a Missing Authentication vulnerability in github.com/openflagr/flagr. A fix is available for github.com/openflagr/flagr — see the affected versions and patch details below.
OpenFlagr <= 1.1.18 Authentication Bypass via Prefix Whitelist Path Normalization
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-0650.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
github.com/openflagr/flagrReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
OpenFlagr versions prior to and including 1.1.18 contain an authentication bypass vulnerability in the HTTP middleware. Due to improper handling of path normalization in the whitelist logic, crafted requests can bypass authentication and access protected API endpoints without valid credentials. Unauthorized access may allow modification of feature flags and export of sensitive data.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/openflagr/flagr | all versions | 0.0.0-20251009103504-fe83dc87aa40go get github.com/openflagr/flagr@v0.0.0-20251009103504-fe83dc87aa40 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/openflagr/flagr, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/openflagr/flagr to 0.0.0-20251009103504-fe83dc87aa40 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-0650 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
How to detect CVE-2026-0650
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2026-0650 -u https://target- Template
- OpenFlagr <= 1.1.18 - Authentication Bypass
- Severity
- critical
- Impact
- Attackers can bypass authentication to modify feature flags and export sensitive data, compromising system integrity and confidentiality.
- Remediation
- Update to the latest version beyond 1.1.18.
Template by ProjectDiscovery nuclei-templates (str4k3r), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2026-0650 in your dependencies?
Find it across Go, including transitive dependencies.