Security readout for executives and security teams
Plain-English summary
CVE-2021-4252 is a low-severity cross-site scripting issue in WP-Ban. A remotely supplied browser user-agent value could be handled unsafely in the ban options area, potentially letting an authenticated attacker influence what another user sees.
Executive priority
Handle in normal vulnerability management cadence unless WP-Ban is deployed on sensitive or high-user-volume sites. Business risk is mainly admin-session abuse or content manipulation, not direct data theft or service outage based on available evidence.
Technical view
The source describes improper handling of $_SERVER["HTTP_USER_AGENT"] in ban-options.php, affecting the toggle_checkbox function. The assigned CVSS 3.1 score is 3.5, with low attack complexity, privileges required, and user interaction required. The named fix is commit 13e0b1e922f3aaa3f8fcb1dd6d50200dd693fd76.
Likely exposure
Exposure is limited to environments running WP-Ban. The source bundle does not identify affected version ranges, package distribution details, or confirmed vulnerable deployment conditions, so asset owners must verify installed plugin code against vendor history.
Exploitation context
The issue is remotely triggerable, but CVSS indicates privileges are required and user interaction is required. The CVE is not listed as KEV in the provided bundle, and no cited source here confirms active exploitation.
Researcher notes
Evidence is incomplete on affected versions. The CVE maps to CWE-707, while the described behavior is cross-site scripting through user-agent handling. Avoid assuming broader WordPress impact beyond WP-Ban without vendor confirmation.
Mitigation direction
- Apply the vendor patch associated with commit 13e0b1e922f3aaa3f8fcb1dd6d50200dd693fd76.
- Check WP-Ban vendor guidance for the fixed release or equivalent remediation.
- Prioritize patching sites where untrusted users can authenticate.
- Limit administrative access to WP-Ban settings until fixed.
Validation and detection
- Inventory production sites for WP-Ban usage and installed version evidence.
- Verify installed code includes the patch commit or equivalent output handling.
- Review ban-options.php for unsafe display of user-agent-derived values.
- Retest in staging with benign user-agent values and confirm encoded output.
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-707: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. 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-2021-4252 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
- Low
- CVSS
- 3.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A: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:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N2.11.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
3.5LowVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/lesterchan/wp-ban/pull/11CVE reference
- https://github.com/lesterchan/wp-ban/commit/13e0b1e922f3aaa3f8fcb1dd6d50200dd693fd76CVE reference
- https://vuldb.com/?id.216209CVE reference
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
Improper Neutralization represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.