Security readout for executives and security teams
Plain-English summary
CVE-2026-0691 affects the WordPress plugin CM E-Mail Blacklist through version 1.6.2. An administrator-level user could save script content in the email blacklist setting, causing it to run later in a browser. Business risk is limited by the need for administrator access and specific WordPress configurations.
Executive priority
Treat as a targeted configuration and privilege-risk issue, not a broad emergency. Prioritize review where the plugin is installed on multisite WordPress environments or where administrator accounts are numerous, shared, or weakly protected.
Technical view
This is a stored cross-site scripting issue in the plugin’s black_email parameter, caused by insufficient input sanitization and output escaping. The CVSS 3.1 score is 4.4. The issue requires authenticated Administrator+ privileges and affects multisite installations or installations where unfiltered_html has been disabled.
Likely exposure
Exposure is mainly WordPress sites using CM E-Mail Blacklist version 1.6.2 or earlier, especially multisite environments or sites that disable unfiltered_html. Single-site deployments with normal administrator unfiltered HTML behavior may not be affected according to the source description.
Exploitation context
No CISA KEV listing is reported in the provided data, and no cited source states active exploitation. Practical exploitation requires an authenticated administrator-level account, so the main concern is malicious, compromised, or misused admin access rather than unauthenticated internet-scale attack.
Researcher notes
The public record identifies the vulnerable parameter and code location, but the provided sources do not state a specific fixed version. The WordPress Trac changeset should be reviewed to confirm remediation details before asserting patch completeness.
Mitigation direction
- Check the plugin vendor or WordPress plugin repository for a patched release.
- Update CM E-Mail Blacklist if a fixed version is available.
- Restrict Administrator and Super Admin access to trusted users only.
- Review whether multisite or disabled unfiltered_html conditions apply.
- Remove unexpected script-like content from plugin blacklist settings.
Validation and detection
- Inventory WordPress sites using CM E-Mail Blacklist.
- Confirm installed plugin versions are 1.6.2 or earlier.
- Identify multisite deployments and sites with unfiltered_html disabled.
- Review blacklist configuration for unexpected or script-like entries.
- Check admin activity logs for suspicious changes to plugin settings.
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-2026-0691 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
- 4.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/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:H/PR:H/UI:N/S:C/C:L/I:L/A:N1.32.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.4MediumVector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/821f4ea9-bc25-4d65-9058-5b77c4f1b230?source=cveCVE reference
- https://plugins.trac.wordpress.org/browser/cm-email-blacklist/trunk/backend/views/settings/email_blacklist.phtml#L67CVE reference
- https://plugins.trac.wordpress.org/browser/cm-email-blacklist/tags/1.6.2/backend/views/settings/email_blacklist.phtml#L67CVE reference
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3440158%40cm-email-blacklist&new=3440158%40cm-email-blacklist&sfp_email=&sfph_mail=CVE 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 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.