Security readout for executives and security teams
Plain-English summary
This is a low-severity stored XSS issue in a WordPress sharing plugin. The attacker must already have administrator-level access, so it is not an easy external takeover path. The main business risk is integrity damage or unwanted script execution inside a site already exposed through privileged account misuse.
Executive priority
Treat as routine remediation unless the organization has many WordPress sites, weak admin controls, or known admin account compromise. Prioritize inventory and cleanup, but this should not displace externally exploitable critical vulnerabilities.
Technical view
CVE-2021-36849 is an authenticated admin+ stored cross-site scripting vulnerability, CWE-79, in René Hermenau's Social Media Share Buttons | MashShare plugin for WordPress versions <= 3.8.1. CVSS v3.1 is 3.4 with PR:H and UI:R, indicating privileged access and user interaction are required.
Likely exposure
Exposure is limited to WordPress sites running Social Media Share Buttons | MashShare version 3.8.1 or earlier. Sites without this plugin, or without affected versions, are not indicated as affected by the supplied sources.
Exploitation context
The supplied data does not show CISA KEV listing or active exploitation. Exploitation requires an authenticated administrator-level user and user interaction, so practical risk is mostly tied to compromised admin accounts, malicious insiders, or weak operational controls around WordPress administrators.
Researcher notes
The evidence identifies affected versions and vulnerability class, but the supplied bundle does not provide exploit details, a named fixed version, or confirmed exploitation. Avoid assuming broader MashShare impact beyond versions <= 3.8.1.
Mitigation direction
- Inventory WordPress sites for the MashShare plugin and record installed versions.
- Check Patchstack and WordPress plugin guidance for the fixed or recommended version.
- Update the plugin if vendor guidance identifies a safe release.
- Disable or remove the plugin where it is not business-critical.
- Restrict WordPress administrator access to trusted, MFA-protected accounts.
Validation and detection
- Confirm whether each WordPress site runs MashShare version 3.8.1 or earlier.
- Review administrator accounts for unnecessary access or weak authentication controls.
- Verify the plugin is updated, disabled, or removed on exposed sites.
- Inspect plugin-managed content/settings for unexpected script-like content.
- Record remediation evidence in vulnerability management tracking.
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-2021-36849 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
- 3.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/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:H/UI:R/S:C/C:N/I:L/A:N1.71.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
3.4LowVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://patchstack.com/database/vulnerability/mashsharer/wordpress-social-media-share-buttons-plugin-3-8-1-authenticated-stored-cross-site-scripting-xss-vulnerabilityCVE reference · x_refsource_CONFIRM
- https://wordpress.org/plugins/mashsharer/#developersCVE 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.