CVE-2026-13358 (GCVE-0-2026-13358)
Vulnerability from cvelistv5 – Published: 2026-08-16 04:24 – Updated: 2026-08-17 19:28
VLAI
EPSS
VEX
Title
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin <= 1.6.12.10 - Authenticated (Contributor+) Insecure Direct Object Reference to Sensitive Information Exposure
Summary
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.10 via the ssa_past_appointments due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with contributor-level access and above, to access appointment records belonging to arbitrary users and harvest the per-appointment ownership tokens (32-character hashes) embedded in the rendered HTML, which can then be used without any authentication to read or modify those appointments including full customer PII such as name, email, phone number, and private notes. The /wp-json/ssa/v1/render-shortcode REST endpoint is registered unconditionally on rest_api_init regardless of whether the Divi theme is installed, and its permission callback only requires current_user_can('edit_posts'), meaning any Contributor-level account is sufficient to trigger this entire exploit chain.
Severity
6.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-17 19:25 UTC
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
12 references
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| croixhaug | Simply Schedule Appointments |
Affected:
0 , ≤ 1.6.12.10
(semver)
|
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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