CVE-2026-19856: CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') in All in One SEO
CVE-2026-19856 is a vulnerability in the All in One SEO WordPress plugin versions before 5.0.2.1. It allows unauthenticated users to execute arbitrary shortcodes because the plugin does not properly identify which shortcodes are present in user-derived content before stripping them. On sites upgraded from older versions, the protection is disabled entirely, making exploitation possible without crafted input.
AI Analysis
Technical Summary
The All in One SEO WordPress plugin prior to version 5.0.2.1 fails to correctly determine which shortcodes exist in content derived from user input before deciding which shortcodes to remove. This improper neutralization of special elements (CWE-74) allows unauthenticated attackers to execute arbitrary shortcodes registered on the site. Additionally, sites upgraded from older versions have this protection disabled outright, increasing the risk of exploitation without requiring crafted input.
Potential Impact
An unauthenticated attacker can execute arbitrary shortcodes on the affected WordPress site. This could lead to unauthorized actions depending on the functionality of the shortcodes registered on the site. The CVSS score of 6.5 (medium severity) reflects limited confidentiality and integrity impact with no availability impact.
Mitigation Recommendations
A fix is available in All in One SEO version 5.0.2.1. Users should upgrade to version 5.0.2.1 or later to remediate this vulnerability. No other mitigation guidance is provided.
CVE-2026-19856: CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') in All in One SEO
Description
CVE-2026-19856 is a vulnerability in the All in One SEO WordPress plugin versions before 5.0.2.1. It allows unauthenticated users to execute arbitrary shortcodes because the plugin does not properly identify which shortcodes are present in user-derived content before stripping them. On sites upgraded from older versions, the protection is disabled entirely, making exploitation possible without crafted input.
CVSS v3.1
Score 6.5medium
Affected software
All in One SEO
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The All in One SEO WordPress plugin prior to version 5.0.2.1 fails to correctly determine which shortcodes exist in content derived from user input before deciding which shortcodes to remove. This improper neutralization of special elements (CWE-74) allows unauthenticated attackers to execute arbitrary shortcodes registered on the site. Additionally, sites upgraded from older versions have this protection disabled outright, increasing the risk of exploitation without requiring crafted input.
Potential Impact
An unauthenticated attacker can execute arbitrary shortcodes on the affected WordPress site. This could lead to unauthorized actions depending on the functionality of the shortcodes registered on the site. The CVSS score of 6.5 (medium severity) reflects limited confidentiality and integrity impact with no availability impact.
Mitigation Recommendations
A fix is available in All in One SEO version 5.0.2.1. Users should upgrade to version 5.0.2.1 or later to remediate this vulnerability. No other mitigation guidance is provided.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- WPScan
- Date Reserved
- 2026-08-14T09:46:29.642Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6abffc19a43b0b3b89ec15b1
Added to database: 10/02/2026, 18:46:49 UTC
Last enriched: 10/02/2026, 19:01:52 UTC
Last updated: 10/02/2026, 19:05:58 UTC
Views: 2
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