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CVE Record

CVE-2020-18659: Cross Site Scripting vulnerability in GetSimpleCMS <=3.3.15 via the (1) sitename, (2) username, and (3) ema...

Cross Site Scripting vulnerability in GetSimpleCMS <=3.3.15 via the (1) sitename, (2) username, and (3) email parameters to /admin/setup.php

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2020-18659 is a cross-site scripting issue in GetSimpleCMS 3.3.15 and earlier. The reported inputs are setup fields for site name, username, and email. A successful attack could cause attacker-controlled script to run in a user’s browser, but the provided sources do not establish active exploitation, CVSS severity, or a confirmed fix.

Executive priority

Handle as a targeted web application hygiene issue, not an emergency based on current evidence. Prioritize externally reachable or business-critical GetSimpleCMS systems, especially where setup endpoints remain accessible.

Technical view

The CVE description identifies XSS through the sitename, username, and email parameters submitted to /admin/setup.php in GetSimpleCMS <=3.3.15. Available source data does not include a CWE, CVSS vector, patch version, or detailed vendor advisory. Treat exposure as tied to vulnerable GetSimpleCMS versions where the setup endpoint remains reachable.

Likely exposure

Likely exposure is GetSimpleCMS 3.3.15 or earlier with /admin/setup.php accessible. Risk may be narrower if the setup workflow is removed, blocked, or unavailable after installation, but the source bundle does not confirm default operational behavior.

Exploitation context

The source bundle describes XSS but provides no KEV listing and no cited evidence of active exploitation. Public references include issue and vulnerability database entries, so defenders should assume technical details may be publicly discoverable without treating it as confirmed exploited.

Researcher notes

Evidence is sparse. The CVE record names parameters and endpoint but lacks CVSS, CWE, affected CPEs, and remediation detail. Validate against the referenced GitHub issue and vulnerability writeups before assigning exploitability or patch status.

Mitigation direction

  • Review GetSimpleCMS issue #1310 and vendor guidance for fixed versions.
  • Apply a vendor-confirmed upgrade or patch when identified.
  • Restrict access to /admin/setup.php where operationally safe.
  • Remove setup components only if vendor documentation supports doing so.
  • Prioritize replacement of unsupported GetSimpleCMS 3.3.15 or earlier deployments.

Validation and detection

  • Inventory public and internal GetSimpleCMS installations.
  • Confirm each instance version is above the affected range or patched.
  • Check whether /admin/setup.php is reachable from untrusted networks.
  • Review web logs for unexpected setup endpoint activity.
  • Document compensating controls if no vendor fix is confirmed.
Prepared
Confidence
medium
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2020-18659 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
4Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.