Hi.Events before 1.11.1-beta Server-Side Request Forgery via Unvalidated Webhook Redirects (CVE-2026-76838) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-76838

Hi.Events before 1.11.1-beta Server-Side Request Forgery via Unvalidated Webhook Redirects

Answer in brief

CVE-2026-76838 records a Unknown severity vulnerability in Hi.Events before 1.11.1-beta Server-Side Request Forgery via Unvalidated Webhook Redirects. The current sources do not mark it as known exploited. The current feed maps HiEventsDev/Hi.Events (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 24, 2026Updated Aug 24, 2026Source checked Aug 24, 2026First seen by HOL Aug 24, 2026Material review Aug 24, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps HiEventsDev/Hi.Events (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
HiEventsDev/Hi.Eventsgeneric	>=0 <1.11.1-beta	1.11.1-beta

Recommended response

Check inventory. Check lockfiles and deployed manifests for HiEventsDev/Hi.Events.
Review the reported fix. Update HiEventsDev/Hi.Events to 1.11.1-beta if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 24, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.