Security readout for executives and security teams
Plain-English summary
CVE-2021-24533 is a stored cross-site scripting issue in the WordPress Maintenance plugin before 4.03. A high-privilege user, such as an administrator, could save unsafe content in plugin settings that later runs on the frontend, even when WordPress normally blocks unfiltered HTML.
Executive priority
Treat this as a targeted cleanup item, not an emergency based on available evidence. Prioritize sites with exposed WordPress admin portals, many administrators, shared admin accounts, or known account compromise concerns.
Technical view
The plugin failed to sanitize or escape some settings before version 4.03, creating a CWE-79 stored XSS condition. The reported attacker profile is authenticated and high privilege. The payload is stored through settings and triggered on the frontend. No CVSS score is provided in the source bundle.
Likely exposure
Exposure is limited to WordPress sites running the Maintenance plugin before 4.03. Risk is most relevant where admin accounts are shared, compromised, delegated to third parties, or restricted by disabling unfiltered_html but still trusted to manage plugin settings.
Exploitation context
The source bundle does not show KEV listing or active exploitation evidence. The weakness requires authenticated high-privilege access, which lowers broad internet exposure but can still matter after account compromise or in multi-admin environments.
Researcher notes
Evidence supports authenticated stored XSS in plugin settings before 4.03, triggered on the frontend despite unfiltered_html restrictions. Sources do not provide CVSS, exploit status, or detailed remediation beyond the version boundary implied by “before 4.03.”
Mitigation direction
- Upgrade the Maintenance WordPress plugin to 4.03 or later.
- Review vendor and WPScan guidance for any additional remediation notes.
- Restrict plugin settings access to trusted administrators only.
- Audit administrator accounts for unnecessary or shared access.
- Review stored Maintenance plugin settings for unexpected unsafe content.
Validation and detection
- Inventory WordPress sites using the Maintenance plugin.
- Confirm installed plugin versions are 4.03 or later.
- Check whether untrusted users have administrator-level access.
- Review relevant frontend pages for unexpected script behavior.
- Verify plugin settings are sanitized after upgrade.
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-2021-24533 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/174b2119-b806-4da4-a23d-c19b552c86cbCVE reference · x_refsource_MISC
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.