NVD / CVE Program· CNA Wordfence

CVE-2026-89063: Online Scheduling and Appointment Booking System <= 28.1 - Insecure Direct Object Reference to Unauthenticated Sensitive Data Access and Message Injection via '

Noroxi assessment

Priority: Monitor (action score 30/100)

A ready-made attack module is public (Nuclei); exploiting it takes no special expertise.
Public proof-of-concept code exists (Exploit-DB / GitHub); there is no record of exploitation in the wild.
Probability of exploitation in the next 30 days: 1.6% (FIRST EPSS); higher than 76% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
According to the record, no fixed version is available yet.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 28.1 via the 'conversation_id' parameter due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers to read the full AI booking conversation transcript of any customer — leaking names, email addresses, phone numbers, and appointment details echoed by the assistant — and inject arbitrary messages into any victim conversation that are subsequently replayed to the Cloud AI worker along with the full private history. Because AI conversations are stored with no owner, user, or session identifier and conversation IDs are sequential integers, an unauthenticated attacker can enumerate all customer conversations simply by incrementing the conversation_id parameter.

HighCVSS 7.5 · v3.1—Proof of concept No fix recorded

EUVD-2026-80112

Published: Sep 16, 2026
Updated: Sep 17, 2026
EPSS: 1.6% · 76th percentile
CWE: CWE-639

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 1.6%

CISA SSVC decision

Exploitation: none
Automatable: yes
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · Wordfence: 7.5; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Is Online Scheduling and Appointment Booking System – Bookly on your site?

WP Lens reads your site's plugin, theme and WordPress versions from the outside and matches them to known vulnerabilities. Works without an account.

If any of these changes, we'll tell you in the daily email digest.

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

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Versions reported by the vendor

Affected version ranges reported by the assigning authority (Wordfence). Independent of NVD's CPE analysis and usually ahead of it.

ladela Online Scheduling and Appointment Booking System – Bookly
- up to and including 28.1affected · semver

Same product

ladela: all records

Other highest-scoring records for the same primary product.

CVE-2026-93399Online Scheduling and Appointment Booking System <= 28.2 - Insecure Direct Object Reference to Unauthenticated Arbitrary Booking Token Disclosure and Deletion v
36Monitor
CVE-2026-14516Online Scheduling and Appointment Booking System <= 27.5 - Unauthenticated SQL Injection
30Monitor
CVE-2026-12626Online Scheduling and Appointment Booking System <= 28.2 - Authenticated (Custom+) PHP Object Injection via 'value' Parameter
28Monitor

Published before and after this one in the same product

← EarlierCVE-2026-13424Aug 16, 2026 · Online Scheduling and Appointment Booking System <= 27.7 - Unauthenticated Stored Cross-Site Scripting via bookly_speed_up_update_addons AJAX action
28Monitor
← EarlierCVE-2026-2520Sep 8, 2026 · Online Scheduling and Appointment Booking System – Bookly <= 27.2 - Missing Authorization to Authenticated (Subscriber+) Limited Arbitrary Plugin Update
21Monitor
Later →CVE-2026-92799Sep 25, 2026 · Online Scheduling and Appointment Booking System <= 28.2 - Unauthenticated Authorization Bypass via PHP Type Juggling via 'verification_code' Parameter Type Jug
21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

Nuclei detection template ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Nuclei detection template	Nuclei template CVE-2026-89063	—

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

jtb75finder

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-933999 days apartOnline Scheduling and Appointment Booking System <= 28.2 - Insecure Direct Object Reference to Unauthenticated Arbitrary Booking Token Disclosure and Deletion v
36Monitor
CVE-2026-10489824 days apartOnline Scheduling and Appointment Booking System <= 28.4 - Insecure Direct Object Reference to Authenticated (Subscriber+) Privilege Escalation via 'id' and 'wp
27Monitor
CVE-2026-1290531 days apartOnline Scheduling and Appointment Booking System – Bookly <= 27.7 - Authenticated (Staff+) Insecure Direct Object Reference to Sensitive Information Exposure vi
17Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

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Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-26-1103 · Sep 16, 2026(WordPress Eklenti Güvenlik Bildirimi)

All national notices →

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: none
Availability: none

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: None
Availability impact: None

Weakness class (CWE)

CWE-639 · Authorization Bypass Through User-Controlled Key

CVSS vector

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

nvd-secondary

Root cause

The endpoint fetches the record by the ID sent in the request, but never checks whether the record belongs to the requesting user.

The bug in code

The whole CWE-639 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const invoice = await Invoice.findById(req.params.id);
2res.json(invoice);

Fixed

1const invoice = await Invoice.findOne({
2  id: req.params.id,
3  ownerId: req.user.id,
4});
5if (!invoice) return res.sendStatus(404);
6res.json(invoice);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/28.1/frontend/modules/ai/Ajax.php#L212

Show all references (5 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records