VDB-407867 · CVE-2026-91847 · EUVD-2026-83509

Online Scheduling and Appointment Booking System Plugin authorization

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.0	$0-$5k	2.96-

Summaryinfo

A vulnerability was found in Online Scheduling and Appointment Booking System Plugin up to 28.1. It has been classified as critical. This impacts an unknown function. The manipulation leads to authorization. This vulnerability is uniquely identified as CVE-2026-91847. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Online Scheduling and Appointment Booking System Plugin up to 28.1 and classified as critical. This issue affects an unknown code block. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The Online Scheduling and Appointment Booking System WordPress plugin before 28.2 does not verify that the requester owns the AI booking-assistant conversation named in its unauthenticated conversation actions, allowing any unauthenticated visitor to read another visitor's assistant messages and to inject messages into their in-progress conversation.

It is possible to read the advisory at wpscan.com. The identification of this vulnerability is CVE-2026-91847 since 09/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 28.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-83509). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

WordPress Plugin

Name

Online Scheduling and Appointment Booking System Plugin

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Online Scheduling and Appointment Booking System Plugin 28.2

Timelineinfo

09/15/2026 CVE reserved
09/19/2026 +4 days Advisory disclosed
09/19/2026 +0 days VulDB entry created
09/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wpscan.com
Status: Confirmed

CVE: CVE-2026-91847 (🔒)
GCVE (CVE): GCVE-0-2026-91847
GCVE (VulDB): GCVE-100-407867
EUVD: 🔒

Entryinfo

Created: 09/19/2026 08:44
Updated: 09/19/2026 09:38
Changes: 09/19/2026 08:44 (54), 09/19/2026 09:38 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.