CVE-2023-22621 — @strapi/plugin-users-perm…
CRITICALCVE-2023-22621 is a critical-severity (CVSS 10) CWE-74 vulnerability in @strapi/plugin-users-permissions. 3 public exploit references exist, so weaponization risk is real. A fix is available for @strapi/plugin-users-permissions — see the affected versions and patch details below.
Strapi plugins vulnerable to Server-Side Template Injection and Remote Code Execution in the Users-Permissions Plugin
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-2023-22621.
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-2023-22621 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE sits: patch-first territory.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@strapi/plugin-users-permissionsnpm@strapi/plugin-emailnpmDescription
Strapi through 4.5.5 allows authenticated Server-Side Template Injection (SSTI) that can be exploited to execute arbitrary code on the server. A remote attacker with access to the Strapi admin panel can inject a crafted payload that executes code on the server into an email template that bypasses the validation checks that should prevent code execution.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @strapi/plugin-users-permissions | all versions | 4.5.6npm install @strapi/plugin-users-permissions@4.5.6 |
| 📦npm | @strapi/plugin-email | all versions | 4.5.6npm install @strapi/plugin-email@4.5.6 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @strapi/plugin-users-permissions, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @strapi/plugin-users-permissions to 4.5.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-22621 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-2023-22621 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-22621. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2023-22621
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2023-22621 -u https://target- Template
- Strapi Versions <=4.5.5 - SSTI to Remote Code Execution
- Severity
- high
- Impact
- Authenticated attackers with admin panel access can inject malicious template code in email templates that bypasses validation checks, executing arbitrary system commands on the Strapi server and potentially compromising the entire CMS platform.
- Remediation
- Update Strapi to version 4.5.6 or later that implements proper template validation and prevents code execution in email templates.
Template by ProjectDiscovery nuclei-templates (iamnoooob, rootxharsh, pdresearch), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2023-22621 in your dependencies?
O3 Security finds CVE-2023-22621 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.