Blind server-side requests via unvalidated webhook URLs
Published Aug 21, 2026 · Updated Aug 21, 2026
Server-side request forgery in ThemeWinter Eventin before 4.1.21 allows remote authenticated users to trigger blind requests to arbitrary hosts. Event webhook handling accepts a user-supplied destination URL and initiates the request without validating the URL or confirming ownership of the referenced event. Contributor-level access is sufficient, and the documented consequence is limited to making the WordPress host contact an attacker-chosen destination.
Summary
What happened
Server-side request forgery in ThemeWinter Eventin before 4.1.21 allows remote authenticated users to trigger blind requests to arbitrary hosts. Event webhook handling accepts a user-supplied destination URL and initiates the request without validating the URL or confirming ownership of the referenced event. Contributor-level access is sufficient, and the documented consequence is limited to making the WordPress host contact an attacker-chosen destination.
The record
- CVE
- CVE-2026-13176
- Published
- Aug 21, 2026
- Updated
- Aug 21, 2026
- Vendor
- ThemeWinter
- Product
- Eventin
- Classifications
- CWE-918
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 21, 2026CVE publishedPublication date reported by the CVE source.
- Aug 21, 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.
- Affected versionversion=0 <4.1.21
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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