CVE-2026-59148 is a high-severity (CVSS 8.8) Missing Authentication vulnerability. O3 Security confirms whether CVE-2026-59148 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Mockoon: Unauthenticated admin API + wildcard CORS allows mock-state hijack and secret theft
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.
- 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-2026-59148.
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-2026-59148 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 371,625 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.
Description
Mockoon provides way to design and run mock APIs. Prior to 9.7.0, Mockoon's admin API in commons-server/src/libs/server/admin-api.ts is mounted on the same Express listener as user-defined mock routes, enabled by default in shipped runtimes, serves Access-Control-Allow-Origin: * with write methods allowed, and has no authentication. Any unauthenticated caller who can reach the mock server port can read MOCKOON_* environment variables, write arbitrary process environment variables through /mockoon-admin/env-vars, rewrite mock route bodies, statuses, and headers through PUT /mockoon-admin/environment, read transaction logs and SSE streams, and purge state. This issue is fixed in version 9.7.0.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-59148 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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 pinpoints whether CVE-2026-59148 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-59148. 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-2026-59148 in your dependencies?
O3 detects CVE-2026-59148 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.