Security readout for executives and security teams
Plain-English summary
This is a stored cross-site scripting issue in the KJM Admin Notices WordPress plugin. An authenticated administrator could save script content through plugin parameters. The main business concern is abuse inside WordPress environments where administrators are not supposed to post unfiltered HTML, especially multisite deployments.
Executive priority
Treat as a moderate-priority cleanup item. It is not an unauthenticated internet-wide emergency, but it weakens administrative trust boundaries and should be removed or remediated on affected WordPress sites.
Technical view
CVE-2021-39344 affects KJM Admin Notices up to and including 2.0.1. The reported weakness is insufficient input validation and sanitization in admin/class-kjm-admin-notices-admin.php, mapped to CWE-79. CVSS 3.1 is 5.5 with high privileges required, low attack complexity, changed scope, and low confidentiality and integrity impact.
Likely exposure
Exposure is limited to WordPress sites running KJM Admin Notices version 2.0.1 or earlier, especially multisite installations or configurations where unfiltered_html is disabled for administrators.
Exploitation context
The source bundle does not show CISA KEV listing or other cited evidence of active exploitation. Exploitation requires authenticated administrative access, reducing broad external risk but still mattering where admin roles are delegated or constrained.
Researcher notes
The key security boundary is constrained administrator behavior, not anonymous compromise. The public sources identify the affected plugin file and validation/sanitization failure, but the provided bundle does not name a fixed version or vendor patch status.
Mitigation direction
- Inventory WordPress sites for KJM Admin Notices versions 2.0.1 or earlier.
- Check vendor or WordPress plugin guidance for a fixed release or official remediation.
- Disable or remove the plugin if no maintained fixed version is available.
- Restrict administrator accounts to trusted users and review delegated admin access.
- Keep WordPress, plugins, and security controls current across multisite environments.
Validation and detection
- Confirm whether KJM Admin Notices is installed and record the active version.
- Identify multisite deployments and sites with unfiltered_html disabled for administrators.
- Review administrative users for unnecessary or stale elevated access.
- Check plugin-managed notices for unexpected script-like content.
- Monitor WordPress administrative activity for suspicious notice changes.
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-2021-39344 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
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/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:H/UI:N/S:C/C:L/I:L/A:N2.32.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39344CVE reference · x_refsource_MISC
- https://github.com/BigTiger2020/word-press/blob/main/KJM%20Admin%20Notices.mdCVE reference · x_refsource_MISC
- https://plugins.trac.wordpress.org/browser/kjm-admin-notices/trunk/admin/class-kjm-admin-notices-admin.phpCVE 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.