CVE-2026-13175Network attack vector

Unauthorized schedule tampering via ownership check omission

Published Aug 19, 2026 · Updated Aug 19, 2026

Authorization bypass in Eventin before 4.1.21 allows remote authenticated users to alter or delete other users' schedule entries. The schedule update and delete paths accept a user-supplied schedule identifier but do not verify that the current contributor owns the referenced record before applying the change. Contributor-level access is required, and the documented impact is unauthorized modification or removal of schedule data rather than code execution or broader role escalation.

CVSS severity6.5
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in Eventin before 4.1.21 allows remote authenticated users to alter or delete other users' schedule entries. The schedule update and delete paths accept a user-supplied schedule identifier but do not verify that the current contributor owns the referenced record before applying the change. Contributor-level access is required, and the documented impact is unauthorized modification or removal of schedule data rather than code execution or broader role escalation.

The record

CVE
CVE-2026-13175
Published
Aug 19, 2026
Updated
Aug 19, 2026
Vendor
ThemeWinter
Product
Eventin
Classifications
CWE-639
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 19, 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 <4.1.21

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ThemeWinter · Eventinversion=0 <4.1.21

Published CVSS scores

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

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.

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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

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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