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TI-2021-22352 Aliases CVE-2021-47735GHSA-9q7q-6c8f-q8gh

CMSimple 5.4 Authenticated Remote Code Execution via Template Editing

Priority HIGH 72CWE-94Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-94.

Summary

CMSimple 5.4 contains an authenticated remote code execution vulnerability that allows logged-in attackers to inject malicious PHP code into template files. Attackers can exploit the template editing functionality by crafting a reverse shell payload and saving it through the template editing endpoint with a valid CSRF token.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00884 59th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA and NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CmsimpleCmsimple5.4—No fix listedCNA
  • Cmsimple VendorCmsimple Affected 5.4 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:cmsimple:cmsimple:5.4:*:*:*:*:*:*:*5.4VulnerableCmsimple
  • cpe:2.3:a:cmsimple:cmsimple:5.4:*:*:*:*:*:*:* Versions 5.4 Vulnerable ·Cmsimple

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-47735
  2. 2026-10-03 Alias added: GHSA-9q7q-6c8f-q8gh

References

Exploit 1

Other 1

  • TI-2024-37939 CMSimple 5.16 allows the user to edit log.php file via print page. CVSS 3.1CRITICAL 9.1
  • TI-2024-37940 CMSimple 5.16 allows the user to read cms source code through manipulation of the file… CVSS 3.1HIGH 7.5
  • TI-2024-37938 Insecure Permissions vulnerability in CMSimple v.5.16 allows a remote attacker to obtain… CVSS 3.1HIGH 7.5
  • TI-2024-37937 An issue in CMSimple v.5.16 allows a remote attacker to obtain sensitive information via… CVSS 3.1HIGH 7.5
  • TI-2021-22351 CMSimple 5.4 Authenticated Local File Inclusion Remote Code Execution CVSS 4.0HIGH 8.6
  • TI-2024-22055 Cross-Site Scripting (XSS) vulnerability in the Settings menu of CMSimple v5.15 allows… CVSS 3.1HIGH 7.4
See all 18 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences