Security readout for executives and security teams
Plain-English summary
CVE-2021-47918 is a high-severity SQL injection issue in Simplephpscripts Simple CMS 2.1. A logged-in, low-privileged attacker could send crafted input to the users module through admin.php and potentially compromise the application database. The bundle does not provide evidence of active exploitation or a confirmed fixed version.
Executive priority
Treat as a high-priority remediation item for any internet-facing or broadly accessible Simple CMS 2.1 admin deployment. Prioritize access restriction immediately, then confirm vendor patch or replacement guidance.
Technical view
The vulnerability is CWE-89 SQL Injection in Simple CMS 2.1, affecting the users module and unvalidated input parameters handled by admin.php. The CVSS v4.0 score is 8.6 with network attack vector, low complexity, no user interaction, and low privileges required. Expected impact is high confidentiality and integrity impact to the vulnerable application's database, with no availability impact stated in the CVSS vector.
Likely exposure
Exposure is limited to deployments running Simplephpscripts Simple CMS version 2.1, especially where the administrative users module is reachable by authenticated users with low privileges. Systems not running Simple CMS 2.1 are listed as unaffected by default in the provided affected-product data.
Exploitation context
The source bundle includes an exploit-tagged Vulnerability Lab reference, but KEV is false and the bundle does not state active exploitation in the wild. Exploitation requires authenticated low-privileged access and targets unvalidated input in the admin.php users module. No exploit payloads or offensive steps are provided here.
Researcher notes
The CVE is unusual in that it was published in 2026 while assigned a 2021 identifier. The supplied data identifies only Simple CMS 2.1 as affected and provides no confirmed fix version. Do not claim active exploitation based only on an exploit-tagged reference.
Mitigation direction
- Inventory any Simple CMS deployments and confirm whether version 2.1 is in use.
- Check Simplephpscripts and advisory guidance for a patched version or vendor-recommended remediation; the bundle does not include patch evidence.
- Restrict access to admin.php and the users module to trusted administrative users and networks where possible.
- Remove unnecessary low-privileged admin access and review role assignments for least privilege.
- If maintaining the application code, remediate SQL handling with parameterized queries and strict server-side input validation.
- Ensure the application database account has only the privileges required by the CMS, reducing impact if injection is exploited.
Validation and detection
- Confirm whether any asset runs Simplephpscripts Simple CMS 2.1.
- Verify whether the users module and admin.php are reachable by low-privileged authenticated users.
- Review vendor or advisory pages for fixed-version information before planning upgrade or patch work.
- Review application and database logs for unusual authenticated activity against the users module, without assuming compromise solely from version presence.
- After remediation, perform authorized defensive testing in a staging or controlled environment to confirm SQL injection is no longer possible.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-89: Database access and collection lookup
Injection into data stores can inform collection, data access, and exfiltration detection reviews. 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 lookupDatabase behavior lookup
The CVE wording references database injection or access, so collection and exfiltration review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-47918 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.6 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
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.
CVSS vector scores
1 official scoreWe 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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
8.6HighVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- Vulnerability Lab AdvisoryCVE reference · exploit
- Product HomepageCVE reference · product
- VulnCheck Advisory: Simple CMS 2.1 SQL Injection Vulnerability via Users ModuleCVE reference · third-party-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.