Security readout for executives and security teams
Plain-English summary
CVE-2021-4424 affects the Slider Hero WordPress plugin up to and including version 8.2.0. If an administrator is tricked into interacting with a malicious link or page while authenticated, an attacker could duplicate slides. The expected business impact is limited content integrity disruption, not data theft or system takeover based on the provided sources.
Executive priority
Treat this as a moderate-priority WordPress hygiene issue. It is not presented as actively exploited or capable of data theft in the supplied sources, but affected public sites should be updated because administrator interaction can still cause unauthorized content changes.
Technical view
The issue is CWE-352 cross-site request forgery caused by missing or incorrect nonce validation in qc_slider_hero_duplicate(). The CVSS v3.1 score is 4.3, with network access, low complexity, no privileges required by the attacker, and required administrator interaction. The described impact is low integrity only.
Likely exposure
Exposure is limited to WordPress sites running Slider Hero with Video Background, Animation at version 8.2.0 or earlier. Sites without this plugin, or with a confirmed patched later release, are not indicated as exposed by the provided bundle.
Exploitation context
The source bundle does not show CISA KEV listing or confirmed active exploitation. Successful exploitation requires tricking an authenticated site administrator into taking an action that causes a forged request. The stated unauthorized action is duplicating slides.
Researcher notes
The public description is narrow: CSRF in a specific duplicate-slide function, with integrity-only impact. The affected-version evidence says up to and including 8.2.0, but the supplied bundle does not clearly name a specific fixed release. Avoid broad claims beyond Slider Hero and the documented duplicate-slide action.
Mitigation direction
- Inventory WordPress sites for the Slider Hero plugin and installed version.
- Upgrade beyond version 8.2.0 if a vendor-confirmed patched release is available.
- If patch status is unclear, check vendor and WordPress plugin guidance before deployment.
- Restrict administrator browsing from active WordPress sessions where practical.
- Review unexpected slide duplication or content changes on affected sites.
Validation and detection
- Confirm whether Slider Hero is installed and active on each WordPress site.
- Verify installed versions are not 8.2.0 or earlier.
- Review the vendor diff for nonce validation around qc_slider_hero_duplicate().
- Check administrative activity logs for unexpected slide duplication events.
- Confirm the site behavior after update in a staging environment.
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-352: 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-2021-4424 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
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/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:N/UI:R/S:U/C:N/I:L/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/e6d195cd-4df8-4926-b834-d695fc05f81d?source=cveCVE reference
- https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/CVE reference
- https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/CVE reference
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/CVE reference
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/CVE reference
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/CVE reference
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/CVE reference
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/CVE reference
- https://plugins.trac.wordpress.org/changeset/2548890/slider-hero/trunk/qcld-slider-main.phpCVE 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.
Cross-Site Request Forgery (CSRF)
Cross-Site Request Forgery (CSRF) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.