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TI-2021-22350 Aliases CVE-2021-47733GHSA-m47r-hm3g-h92f

CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding

Priority MEDIUM 56CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

CMSimple 5.4 contains a cross-site scripting vulnerability that allows attackers to bypass input filtering by using HTML to Unicode encoding. Attackers can inject malicious scripts by encoding payloads like ')-alert(1)// and execute arbitrary JavaScript when victims interact with delete buttons.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00264 18th 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
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
CmsimpleCMSimpleup to 5.4—No fix listedCNA
  • CMSimple VendorCmsimple Affected up to 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-2021-47733
  2. 2026-10-03 Alias added: GHSA-m47r-hm3g-h92f

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-2021-22352 CMSimple 5.4 Authenticated Remote Code Execution via Template Editing CVSS 4.0HIGH 8.6
  • TI-2021-22351 CMSimple 5.4 Authenticated Local File Inclusion Remote Code Execution CVSS 4.0HIGH 8.6
See all 18 →

Sources

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