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CVE Record

CVE-2021-47919: Simple CMS 2.1 Non-Persistent Cross-Site Scripting via Preview Parameter

Simple CMS 2.1 contains a non-persistent cross-site scripting vulnerability in the preview.php file's id parameter. Attackers can inject malicious script code through a GET request to execute arbitrary scripts and potentially hijack user sessions or perform phishing attacks.

MediumCVSS 6.4Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

Simple CMS 2.1 has a reflected, non-persistent cross-site scripting issue in a preview page parameter. If an exposed site uses this product/version, an attacker could cause script execution in a user’s browser, potentially supporting session theft or phishing. This is not listed in CISA KEV, and the provided sources do not prove active exploitation.

Executive priority

Treat as a focused remediation item for any exposed Simple CMS 2.1 deployment. It is not a broad enterprise emergency, but public technical details increase risk if the application is reachable by users or the internet.

Technical view

CVE-2021-47919 affects Simplephpscripts Simple CMS 2.1. The reported flaw is CWE-79 in preview.php via the id GET parameter. CVSS 3.1 is 6.4 with network access, low complexity, low privileges, scope changed, and low confidentiality/integrity impact. Availability impact is not reported.

Likely exposure

Exposure is likely limited to organizations running Simple CMS 2.1, especially if the application is internet-facing or accessible to untrusted users. The CVE record indicates other versions are not affected by default, but local deployments should be verified against vendor and advisory information.

Exploitation context

Public advisories describe the issue and one reference is tagged as exploit, indicating technical details are public. The supplied sources do not establish active exploitation in the wild, and the CVE is not marked as CISA KEV.

Researcher notes

Evidence is limited to the CVE record and public advisories. No patch version is named in the provided bundle. Avoid assuming broader product impact beyond Simple CMS 2.1 unless vendor documentation confirms it.

Mitigation direction

  • Identify whether Simple CMS 2.1 is deployed in any environment.
  • Check vendor guidance and advisory updates for an official fix or supported upgrade path.
  • Restrict access to affected administrative or preview functionality where feasible.
  • Apply compensating controls for reflected XSS, such as input validation and output encoding.
  • Review session security settings to reduce impact from browser-side script execution.

Validation and detection

  • Confirm product name and version from application records or vendor files.
  • Determine whether preview.php is reachable by expected user roles only.
  • Use authorized, non-destructive testing to verify input is safely encoded.
  • Review web logs for unusual requests to the preview page parameter.
  • Document exposure, compensating controls, and remediation status.
Prepared
Confidence
high
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

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · medium confidence lookup

CWE-79: User-session and phishing behavior lookup

Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-47919 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Medium
CVSS
6.4 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

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.

1CVSS vectors
0Timeline events
0ADP providers
4Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
6.4CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N3.12.7Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.4Medium
CVSS 3.1 vector shape for CVE-2021-47919Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
SimplephpscriptsSimple CMS2.1unaffected
Weakness

CWE details

CWE-79

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