Vulnerability-Lookup

FKIE_CVE-2026-76838

Vulnerability from fkie_nvd - Published: 2026-08-24 18:17 - Updated: 2026-08-24 18:17

Severity

8.5 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N

Summary

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.

References

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

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/HiEventsDev/Hi.Events",
          "product": "Hi.Events",
          "repo": "https://github.com/HiEventsDev/Hi.Events",
          "vendor": "HiEventsDev",
          "versions": [
            {
              "lessThan": "1.11.1-beta",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "disclosure@vulncheck.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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\u0027s 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."
    }
  ],
  "id": "CVE-2026-76838",
  "lastModified": "2026-08-24T18:17:22.363",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 8.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 4.7,
        "source": "disclosure@vulncheck.com",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "HIGH",
          "subIntegrityImpact": "LOW",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "disclosure@vulncheck.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-24T18:17:22.363",
  "references": [
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/HiEventsDev/Hi.Events"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/HiEventsDev/Hi.Events/blob/v.1.11.0-beta/backend/app/Validators/Rules/NoInternalUrlRule.php"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/HiEventsDev/Hi.Events/commit/cfbf468bb5b1"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://github.com/HiEventsDev/Hi.Events/pull/1311"
    },
    {
      "source": "disclosure@vulncheck.com",
      "url": "https://www.vulncheck.com/advisories/hi-events-before-beta-server-side-request-forgery-via-unvalidated-webhook-redirects"
    }
  ],
  "sourceIdentifier": "disclosure@vulncheck.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ],
      "source": "disclosure@vulncheck.com",
      "type": "Primary"
    }
  ]
}

CVE-2026-76838 (GCVE-0-2026-76838)

Vulnerability from cvelistv5 – Published: 2026-08-24 17:36 – Updated: 2026-08-24 17:36

Title

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

Summary

Severity

8.4 (High)


                        
                          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

8.5 (High)


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

CWE

CWE-918 - Server-Side Request Forgery (SSRF)

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://github.com/HiEventsDev/Hi.Events	product
https://github.com/HiEventsDev/Hi.Events/pull/1311	issue-tracking
https://github.com/HiEventsDev/Hi.Events/commit/c…	patch
https://github.com/HiEventsDev/Hi.Events/blob/v.1…	technical-description
https://www.vulncheck.com/advisories/hi-events-be…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
HiEventsDev	Hi.Events	Affected: 0 , < 1.11.1-beta (semver) cpe:2.3:a:hi.events:hi.events::::::::

Date Public

2026-08-11 00:00

Credits

@tonghuaroot @de3erve Jaime Ramírez (@JaimeRamirez-coder) @senti-man @angelystor @1amplant @tikket1 @Fewword @dizconnectz

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/HiEventsDev/Hi.Events",
          "product": "Hi.Events",
          "repo": "https://github.com/HiEventsDev/Hi.Events",
          "vendor": "HiEventsDev",
          "versions": [
            {
              "lessThan": "1.11.1-beta",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:hi.events:hi.events:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "1.11.1-beta",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "@tonghuaroot"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@de3erve"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Jaime Ram\u00edrez (@JaimeRamirez-coder)"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@senti-man"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@angelystor"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@1amplant"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@tikket1"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@Fewword"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@dizconnectz"
        }
      ],
      "datePublic": "2026-08-11T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "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\u0027s 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": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.4,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "LOW",
            "userInteraction": "NONE",
            "vectorString": "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "LOW"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 8.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-918",
              "description": "Server-Side Request Forgery (SSRF)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-24T17:36:02.928Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/HiEventsDev/Hi.Events"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/HiEventsDev/Hi.Events/pull/1311"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/HiEventsDev/Hi.Events/commit/cfbf468bb5b1"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/HiEventsDev/Hi.Events/blob/v.1.11.0-beta/backend/app/Validators/Rules/NoInternalUrlRule.php"
        },
        {
          "name": "VulnCheck Advisory: Hi.Events before 1.11.1-beta Server-Side Request Forgery via Unvalidated Webhook Redirects",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/hi-events-before-beta-server-side-request-forgery-via-unvalidated-webhook-redirects"
        }
      ],
      "title": "Hi.Events before 1.11.1-beta Server-Side Request Forgery via Unvalidated Webhook Redirects",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-76838",
    "datePublished": "2026-08-24T17:36:02.928Z",
    "dateReserved": "2026-08-19T20:34:00.155Z",
    "dateUpdated": "2026-08-24T17:36:02.928Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

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FKIE_CVE-2026-76838

CVE-2026-76838 (GCVE-0-2026-76838)

Tags

Sightings

Nomenclature