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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-76838 Detail

Description

Hi.Events validates a webhook destination only when it is registered, never when it is used. NoInternalUrlRule in backend/app/Validators/Rules/NoInternalUrlRule.php resolves the hostname with gethostbyname() and rejects private and reserved ranges, which any public hostname passes. At dispatch, WebhookDispatchService takes the stored URL and calls it through spatie/laravel-webhook-server without repeating the check, and backend/config/webhook-server.php sets no Guzzle options, so redirect following remains enabled by default. A destination that answers with a redirect to a loopback, private or cloud metadata address therefore causes the server to issue that request, and changing the hostname's DNS record after registration reaches the same result because no resolution is repeated. The response is not discarded: WebhookResponseHandlerService stores the body on the webhook log and WebhookLogResource returns it from the webhook logs endpoint, so the requester reads what the internal service replied rather than inferring it. Both event and organizer webhooks share the rule and the dispatch path. Version 1.11.1-beta revalidates at dispatch, pins the validated address, checks every redirect hop, and decodes IPv6 transition addresses that previously bypassed the filter.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  VulnCheck
CVSS-B 8.4 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/HiEventsDev/Hi.Events VulnCheck
https://github.com/HiEventsDev/Hi.Events/blob/v.1.11.0-beta/backend/app/Validators/Rules/NoInternalUrlRule.php VulnCheck
https://github.com/HiEventsDev/Hi.Events/commit/cfbf468bb5b1 VulnCheck
https://github.com/HiEventsDev/Hi.Events/pull/1311 VulnCheck
https://www.vulncheck.com/advisories/hi-events-before-beta-server-side-request-forgery-via-unvalidated-webhook-redirects VulnCheck

Weakness Enumeration

CWE-ID CWE Name Source
CWE-918 Server-Side Request Forgery (SSRF) VulnCheck  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-76838
NVD Published Date:
08/24/2026
NVD Last Modified:
08/24/2026
Source:
VulnCheck