Vulnerability in WordPress (CVE-2026-9188)
Summary
Vulnerability in WordPress (CVE-2026-9188). Risk of unauthorized operations or information disclosure. Exploitable via appointmentkey.
Original description
The description as published by the source.
The Appointment Bookings for Zoom GoogleMeet and more – Wappointment plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to and including 2.7.6 via the appointmentkey parameter due to the appointment edit_key — the sole authorization token consumed by tryCancel() — being generated as a predictable, unsalted MD5 hash of only client_id (a sequential integer), start_at (a publicly observable appointment timestamp), and staff_id (a small enumerable integer), with no secret salt or random component, and the unauthenticated cancellation and rescheduling REST endpoints performing no ownership or identity verification beyond matching this reconstructible key. This makes it possible for unauthenticated attackers to compute valid edit_key values for appointments belonging to other users and cancel or reschedule those appointments arbitrarily. Exploitation requires the allow_cancellation or allow_rescheduling setting to be enabled on the site, both of which are common configurations for active booking deployments; an attacker can obtain the inputs needed to reconstruct a victim's key by booking their own appointment to observe their sequential client_id and correlating publicly visible appointment times and enumerable staff identifiers.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-9188 has been found in WordPress.
Attackers can target a specific entry point like appointmentkey over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "WordPress CVE-2026-9188" on the vendor's site.
CVE-2026-9188 (WordPress) — CWE-639 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: appointmentkey / edit_key / client_id / start_at
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-639) exists in WordPress. Attackers reach the vulnerable code path via appointmentkey without authentication.
Check the vendor advisory for the affected versions of WordPress. Attack surface: appointmentkey / edit_key / client_id / start_at.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで WordPress を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web nvd.nist.gov
- web github.com