CVE-2026-48781 (GCVE-0-2026-48781)

Vulnerability from cvelistv5 – Published: 2026-06-16 21:31 – Updated: 2026-06-18 14:26
VLAI
Title
Postiz has cross-tenant SUPERADMIN takeover via Skool-provider JWT forgery
Summary
Postiz is an AI social media scheduling tool. In versions prior to 2.21.8, the Skool integration callback signed an attacker-controlled JSON blob into a session-shape JWT using the application's JWT_SECRET, and the auth middleware trusted every claim in that JWT without re-resolving the user from the database. Any authenticated Postiz user could forge a SUPERADMIN session and impersonate arbitrary organizations. This allowed Full Access to the following: all parts of Postiz, including users registered to the specific instance and the ability to post in the name of the victim's social media channels added to that Postiz instance. This issue has been fixed in version 2.21.8.
Severity
9.9 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-302 - Authentication Bypass by Assumed-Immutable Data
  • CWE-345 - Insufficient Verification of Data Authenticity
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version
gitroomhq postiz-app Affected: < 2.21.8
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-48781",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-18T14:25:47.270443Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-18T14:26:17.633Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "postiz-app",
          "vendor": "gitroomhq",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.21.8"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Postiz is an AI social media scheduling tool. In versions prior to 2.21.8, the Skool integration callback signed an attacker-controlled JSON blob into a session-shape JWT using the application\u0027s JWT_SECRET, and the auth middleware trusted every claim in that JWT without re-resolving the user from the database. Any authenticated Postiz user could forge a SUPERADMIN session and impersonate arbitrary organizations. This allowed Full Access to the following: all parts of Postiz, including users registered to the specific instance and the ability to post in the name of the victim\u0027s social media channels added to that Postiz instance. This issue has been fixed in version 2.21.8."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.9,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-302",
              "description": "CWE-302: Authentication Bypass by Assumed-Immutable Data",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-345",
              "description": "CWE-345: Insufficient Verification of Data Authenticity",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-863",
              "description": "CWE-863: Incorrect Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-16T21:31:28.955Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-j77w-h625-56q2",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-j77w-h625-56q2"
        },
        {
          "name": "https://github.com/gitroomhq/postiz-app/commit/23696d2973510ae1f3f48bfa41a6bfbbf9827b05",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/gitroomhq/postiz-app/commit/23696d2973510ae1f3f48bfa41a6bfbbf9827b05"
        },
        {
          "name": "https://gadvisory.org/advisories/PSA-2026-2CAQ96",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://gadvisory.org/advisories/PSA-2026-2CAQ96"
        },
        {
          "name": "http://github.com/gitroomhq/postiz-app/releases/tag/v2.21.8",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "http://github.com/gitroomhq/postiz-app/releases/tag/v2.21.8"
        }
      ],
      "source": {
        "advisory": "GHSA-j77w-h625-56q2",
        "discovery": "UNKNOWN"
      },
      "title": "Postiz has cross-tenant SUPERADMIN takeover via Skool-provider JWT forgery"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-48781",
    "datePublished": "2026-06-16T21:31:28.955Z",
    "dateReserved": "2026-05-22T20:18:20.365Z",
    "dateUpdated": "2026-06-18T14:26:17.633Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-48781",
      "date": "2026-06-20",
      "epss": "0.00262",
      "percentile": "0.17338"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-48781\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-06-18T14:25:47.270443Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-06-18T14:26:11.610Z\"}}], \"cna\": {\"title\": \"Postiz has cross-tenant SUPERADMIN takeover via Skool-provider JWT forgery\", \"source\": {\"advisory\": \"GHSA-j77w-h625-56q2\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"CHANGED\", \"version\": \"3.1\", \"baseScore\": 9.9, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"gitroomhq\", \"product\": \"postiz-app\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 2.21.8\"}]}], \"references\": [{\"url\": \"https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-j77w-h625-56q2\", \"name\": \"https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-j77w-h625-56q2\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/gitroomhq/postiz-app/commit/23696d2973510ae1f3f48bfa41a6bfbbf9827b05\", \"name\": \"https://github.com/gitroomhq/postiz-app/commit/23696d2973510ae1f3f48bfa41a6bfbbf9827b05\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://gadvisory.org/advisories/PSA-2026-2CAQ96\", \"name\": \"https://gadvisory.org/advisories/PSA-2026-2CAQ96\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"http://github.com/gitroomhq/postiz-app/releases/tag/v2.21.8\", \"name\": \"http://github.com/gitroomhq/postiz-app/releases/tag/v2.21.8\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Postiz is an AI social media scheduling tool. In versions prior to 2.21.8, the Skool integration callback signed an attacker-controlled JSON blob into a session-shape JWT using the application\u0027s JWT_SECRET, and the auth middleware trusted every claim in that JWT without re-resolving the user from the database. Any authenticated Postiz user could forge a SUPERADMIN session and impersonate arbitrary organizations. This allowed Full Access to the following: all parts of Postiz, including users registered to the specific instance and the ability to post in the name of the victim\u0027s social media channels added to that Postiz instance. This issue has been fixed in version 2.21.8.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-302\", \"description\": \"CWE-302: Authentication Bypass by Assumed-Immutable Data\"}]}, {\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-345\", \"description\": \"CWE-345: Insufficient Verification of Data Authenticity\"}]}, {\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-863\", \"description\": \"CWE-863: Incorrect Authorization\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-06-16T21:31:28.955Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-48781\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-06-18T14:26:17.633Z\", \"dateReserved\": \"2026-05-22T20:18:20.365Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-06-16T21:31:28.955Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.