CVE-2026-13358Network attack vector

Appointment disclosure via unchecked shortcode record key

Published Aug 16, 2026 · Updated Aug 16, 2026

IDOR in Simply Schedule Appointments 1.6.12.10 and earlier allows remote authenticated users to read other users' appointment records. The render-shortcode REST endpoint accepts ssa_past_appointments with a user-controlled record key, renders records without an ownership check, and exposes 32-character ownership tokens in HTML. Contributor-level access is required to harvest a token; token-based appointment actions then accept that token without authentication.

CVSS severity6.5
Medium
EPSS probability0.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

IDOR in Simply Schedule Appointments 1.6.12.10 and earlier allows remote authenticated users to read other users' appointment records. The render-shortcode REST endpoint accepts ssa_past_appointments with a user-controlled record key, renders records without an ownership check, and exposes 32-character ownership tokens in HTML. Contributor-level access is required to harvest a token; token-based appointment actions then accept that token without authentication.

The record

CVE
CVE-2026-13358
Published
Aug 16, 2026
Updated
Aug 16, 2026
Vendor
N Squared Digital, LLC
Product
Simply Schedule Appointments
Classifications
CWE-639, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 16, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=1.6.12.10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

N Squared Digital, LLC · Simply Schedule Appointmentsversion=0 <=1.6.12.10

Published CVSS scores

6.5WordfenceCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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