CVE-2026-19807 (GCVE-0-2026-19807)

Vulnerability from cvelistv5 – Published: 2026-10-01 07:40 – Updated: 2026-10-03 15:42
VLAI
Title
ByteCoreStack <= 1.2.3 - Authenticated (Subscriber+) Privilege Escalation via wp_update_user_meta MCP Tool
Summary
The ByteCoreStack – MCP Connector for AI Tools plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.2.3 This is due to the `wp_update_user_meta` MCP tool in `execute_tool` gating writes solely with `current_user_can('edit_user', $uid)` — a check that WordPress core's `map_meta_cap` resolves to the `read` primitive when the target user ID matches the caller's own — while enforcing an incomplete meta key blocklist that covers only `user_pass`, `user_activation_key`, and `session_tokens`, leaving the `wp_capabilities` and `wp_user_level` meta keys entirely unprotected. This makes it possible for authenticated attackers with Subscriber-level access and above to elevate their privileges to Administrator by issuing a `wp_update_user_meta` call over the MCP JSON-RPC endpoint with `key=wp_capabilities` and an arbitrary role array such as `{'administrator': true}` targeting their own user ID, causing WordPress to load that account as an Administrator on the next request.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-03 15:35 UTC
CWE
  • CWE-269 - Improper Privilege Management
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2309 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
bytecorestack ByteCoreStack – MCP Connector for AI Tools Affected: 0 , ≤ 1.2.3 (semver)
guessed Create a notification for this product.
Credits
Décio Brandão
Show details on NVD website
To clipboard 

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