Security readout for executives and security teams
Plain-English summary
CVE-2021-24574 is a stored cross-site scripting issue in the Simple Banner WordPress plugin before 2.10.4. A privileged user, such as an administrator, could save script content in a plugin setting even where WordPress normally disallows unfiltered HTML.
Executive priority
Treat as a targeted hygiene fix, not an emergency based on the provided evidence. Prioritize shared WordPress environments and sites with multiple administrators because the issue weakens policy controls around script injection.
Technical view
The flaw is CWE-79 in Simple Banner: one setting was not properly sanitized and escaped before storage or output. The reported impact is authenticated stored XSS by high-privilege users, specifically relevant when unfiltered_html is disabled. The bundle indicates the issue was fixed in 2.10.4.
Likely exposure
Exposure is limited to WordPress sites using Simple Banner versions before 2.10.4. Risk is higher on multisite, delegated-admin, or compliance-controlled environments where administrators should not be able to inject active content.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation evidence. Public references identify the vulnerability and a WordPress plugin changeset, but no exploitation-in-the-wild claim is provided here.
Researcher notes
The key issue is missing sanitization and escaping on a setting, allowing stored XSS by high-privilege authenticated users. The affected range is described as before 2.10.4; the supplied affected metadata is less clear, so confirm against vendor records during triage.
Mitigation direction
- Upgrade Simple Banner to 2.10.4 or later.
- Check vendor and WordPress plugin guidance for any newer fixed release.
- Restrict administrator access to trusted users only.
- Review sites where unfiltered_html is intentionally disabled.
- Remove or disable the plugin if it cannot be updated.
Validation and detection
- Inventory WordPress sites for the Simple Banner plugin.
- Confirm installed Simple Banner versions are 2.10.4 or later.
- Review plugin settings for unexpected active content.
- Check WordPress audit logs for recent plugin setting changes.
- Verify administrator accounts are current and authorized.
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-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 lookupCVE-2021-24574 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://wpscan.com/vulnerability/9adf7022-5108-43b7-bf0e-a42593185b74CVE reference · x_refsource_MISC
- https://plugins.trac.wordpress.org/changeset/2571047/CVE reference · x_refsource_CONFIRM
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 Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.