How severe is CVE-2018-21037?

CVE-2018-21037 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2018-21037?

CVE-2018-21037 affects the following packages: intelliants/subrion (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2018-21037?

Update intelliants/subrion to 4.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-21037 is resolved across your whole dependency graph.

How do I detect CVE-2018-21037 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for intelliants/subrion, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2018-21037 if there is no patch (or I can't update yet)?

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.

Is CVE-2018-21037 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2018-21037, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2018-21037?

CVE-2018-21037 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 44th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2018-21037?

CVE-2018-21037 is classified as Cross-Site Request Forgery (CSRF) (CWE-352). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2018-21037 published, and has it been updated?

CVE-2018-21037 was published on March 17, 2020 and was last updated on October 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘

🐘 Packagist

Not in CISA KEV

HIGH severity

CVE-2018-21037 — subrion

HIGH

CVE-2018-21037 is a high-severity (CVSS 8.8) Cross-Site Request Forgery (CSRF) vulnerability in intelliants/subrion. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for intelliants/subrion — see the affected versions and patch details below.

Subrion CMS CSRF Vulnerability

Also known asGHSA-g8j7-w673-4mjp

Published

Mar 17, 2020

Updated

Oct 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

Exploitation data as of Nov 3, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs44th percentile — riskier than 44% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐘intelliants/subrion

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Subrion CMS 4.1.5 (and possibly earlier versions) allow CSRF to change the administrator password via the panel/members/edit/1 URI.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`intelliants/subrion`	all versions	4.2.1`composer require intelliants/subrion:^4.2.1`

Affected Products

1 product · 1 configurations

Application

subrionintelliants

≤ 4.1.5

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Subrion CMS 4.1.5 (and possibly earlier versions) allow CSRF to change t…

github.comNVDMar 2020

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for intelliants/subrion, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update intelliants/subrion to 4.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-21037 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.

Frequently Asked Questions

Subrion CMS 4.1.5 (and possibly earlier versions) allow CSRF to change the administrator password via the panel/members/edit/1 URI.

O3 Security · Impact-Aware SCA

Is CVE-2018-21037 in your dependencies?

Find it across Packagist, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

8.8/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CWE Classification

CWE-352Cross-Site Request Forgery (CSRF)

Weaponization

No Nuclei template or Metasploit module yet. 1 public proof-of-concept reference is listed on this page.

OpenSSF Scorecard

Package health score

subrion

3.9/10

Code-Review9/10

Maintained0/10

Branch-ProtectionN/A

Assessed Nov 2, 2026

Timeline

Disclosed

Mar 17, 2020

First exploit

Mar 20, 2020

3 days after disclosure — rapid exploitation

Last updated

Oct 20, 2026

Identifiers

CVE-2018-21037

GHSA-g8j7-w673-4mjp

References

Advisorynvd.nist.gov · CVE 2018 21037 Webgithub.com · changelog.txt Packagegithub.com · subrion Evidencegithub.com

Related vulnerabilities

This CVE is high severity; 1 of 8 other CVEs affecting intelliants/subrion is rated as high or higher (top: high).

CVE-2026-12202CVE-2025-70958CVE-2025-56556CVE-2024-25399CVE-2023-46947CVE-2023-43875CVE-2023-43884CVE-2023-43828

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 20, 2026

CVE-2018-21037 — subrion

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2018-21037 in your dependencies?