phpMyFAQ CVE-2026-108851

Exploitation requires that the optional phpMyFAQ MCP server feature is enabled and that the attacker can connect to phpmyfaq:mcp:server as an MCP client with at least low-privilege access (CVSS PR:L) - it is not a remote-unauthenticated flaw. The affected feature is specifically the faq_search tool, whose executor calls Search::searchDatabase() without applying the per-user/per-group permission checks that normally restrict FAQ visibility. Exploitation is limited to confidentiality (reading question/answer text of active, access-restricted FAQs); there is no write, modification, or availability impact. Key limiting factors: the MCP server must be deployed and reachable (non-default for many installs), the attacker needs an authenticated/privileged MCP connection, the attack vector is local rather than network-facing, and only FAQs that are active and restricted are exposed.

This is a genuine but modest-priority issue, not a high-urgency flaw. The input CVSS 4.0 base score is 4.8 (Medium) with vector AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - a local attack vector, low complexity, but requiring low-level privileges (PR:L) and yielding only limited confidentiality impact (VC:L) with no integrity or availability impact. In plain terms, an actor who already holds some authenticated access to the MCP server can read restricted FAQ content they should not see; they cannot modify data or crash the service. There is NO EPSS score in the provided data and NO CISA KEV listing, so there is no quantitative exploitation-probability signal and no evidence of active exploitation. No SSVC decision record was supplied either. No explicit POC flag was provided, though VulnCheck and a hackmd write-up document the mechanism (Search::searchDatabase() omitting user/group permission checks). The signals are internally consistent - a low-privilege, local, confidentiality-only authorization gap - so there is no contradiction to flag, but defenders should note the key missing signals (EPSS and KEV absent) mean real-world exploitation likelihood is unquantified and should be treated as low absent further intelligence.

An actor with low-privilege access to a phpMyFAQ instance that has the MCP server enabled connects as an MCP client to phpmyfaq:mcp:server and invokes the faq_search tool. Because Search::searchDatabase() never applies user or group permission filters, the search returns the full question and answer text of FAQs that were restricted to specific users or groups, disclosing information the actor was not authorized to read. No public exploit identified at time of analysis, though the vulnerable code paths are documented in the references.