Vulnerability-Lookup

GHSA-49M8-524G-8RR2

Vulnerability from github – Published: 2026-08-05 09:31 – Updated: 2026-08-05 09:31

Details

The MailChimp Forms by MailMunch plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the sign_in() and sign_up() AJAX handlers in all versions up to, and including, 3.2.7. This makes it possible for authenticated attackers, with Subscriber-level access and above, to relink the site's MailMunch integration to an attacker-controlled MailMunch account by submitting attacker-supplied credentials. Once relinked, all subscriber data captured by the plugin's forms is delivered to the attacker, and the forms/landing pages rendered on the site are pulled from the attacker's MailMunch account.

Severity

8.1 (High)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-7520"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-862"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-05T08:16:44Z",
    "severity": "HIGH"
  },
  "details": "The MailChimp Forms by MailMunch plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `sign_in()` and `sign_up()` AJAX handlers in all versions up to, and including, 3.2.7. This makes it possible for authenticated attackers, with Subscriber-level access and above, to relink the site\u0027s MailMunch integration to an attacker-controlled MailMunch account by submitting attacker-supplied credentials. Once relinked, all subscriber data captured by the plugin\u0027s forms is delivered to the attacker, and the forms/landing pages rendered on the site are pulled from the attacker\u0027s MailMunch account.",
  "id": "GHSA-49m8-524g-8rr2",
  "modified": "2026-08-05T09:31:19Z",
  "published": "2026-08-05T09:31:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-7520"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/admin/class-mailchimp-mailmunch-admin.php#L126"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/admin/class-mailchimp-mailmunch-admin.php#L134"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/includes/class-mailchimp-mailmunch.php#L219"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/includes/class-mailmunch-api.php#L354"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/includes/class-mailmunch-api.php#L371"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/trunk/admin/class-mailchimp-mailmunch-admin.php#L134"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026new=3593826%40mailchimp-forms-by-mailmunch%2Ftags%2F3.2.8\u0026old=3445363%40mailchimp-forms-by-mailmunch%2Ftags%2F3.2.7"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/c9d00ee8-b9df-4044-a5e2-320391d6c9b1?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-7520 (GCVE-0-2026-7520)

Vulnerability from cvelistv5 – Published: 2026-08-05 07:39 – Updated: 2026-08-05 13:11

Title

MailChimp Forms by MailMunch <= 3.2.7 - Missing Authorization to Authenticated (Subscriber+) MailMunch Integration Takeover via 'sign_in' AJAX Action

Summary

The MailChimp Forms by MailMunch plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `sign_in()` and `sign_up()` AJAX handlers in all versions up to, and including, 3.2.7. This makes it possible for authenticated attackers, with Subscriber-level access and above, to relink the site's MailMunch integration to an attacker-controlled MailMunch account by submitting attacker-supplied credentials. Once relinked, all subscriber data captured by the plugin's forms is delivered to the attacker, and the forms/landing pages rendered on the site are pulled from the attacker's MailMunch account.

Severity

8.1 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-05 13:11 UTC

CWE

CWE-862 - Missing Authorization

Assigner

Wordfence mitre root

References

8 references

URL	Tags
https://www.wordfence.com/threat-intel/vulnerabil…
https://plugins.trac.wordpress.org/browser/mailch…
https://plugins.trac.wordpress.org/browser/mailch…
https://plugins.trac.wordpress.org/browser/mailch…
https://plugins.trac.wordpress.org/browser/mailch…
https://plugins.trac.wordpress.org/browser/mailch…
https://plugins.trac.wordpress.org/browser/mailch…
https://plugins.trac.wordpress.org/changeset?sfp_…

Impacted products

1 product

Vendor	Product	Version
mailmunch	Mailmunch Forms for Mailchimp	Affected: 0 , ≤ 3.2.7 (semver)

Credits

t0ann9uy3n

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-7520",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-05T13:11:17.915405Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-05T13:11:29.519Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mailmunch Forms for Mailchimp",
          "vendor": "mailmunch",
          "versions": [
            {
              "lessThanOrEqual": "3.2.7",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "t0ann9uy3n"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The MailChimp Forms by MailMunch plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `sign_in()` and `sign_up()` AJAX handlers in all versions up to, and including, 3.2.7. This makes it possible for authenticated attackers, with Subscriber-level access and above, to relink the site\u0027s MailMunch integration to an attacker-controlled MailMunch account by submitting attacker-supplied credentials. Once relinked, all subscriber data captured by the plugin\u0027s forms is delivered to the attacker, and the forms/landing pages rendered on the site are pulled from the attacker\u0027s MailMunch account."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862 Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
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        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T07:39:23.697Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/c9d00ee8-b9df-4044-a5e2-320391d6c9b1?source=cve"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/trunk/admin/class-mailchimp-mailmunch-admin.php#L134"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/admin/class-mailchimp-mailmunch-admin.php#L134"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/admin/class-mailchimp-mailmunch-admin.php#L126"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/includes/class-mailmunch-api.php#L354"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/includes/class-mailmunch-api.php#L371"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/mailchimp-forms-by-mailmunch/tags/3.2.7/includes/class-mailchimp-mailmunch.php#L219"
        },
        {
          "url": "https://plugins.trac.wordpress.org/changeset?sfp_email=\u0026sfph_mail=\u0026reponame=\u0026new=3593826%40mailchimp-forms-by-mailmunch%2Ftags%2F3.2.8\u0026old=3445363%40mailchimp-forms-by-mailmunch%2Ftags%2F3.2.7"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-08-04T18:41:47.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "MailChimp Forms by MailMunch \u003c= 3.2.7 - Missing Authorization to Authenticated (Subscriber+) MailMunch Integration Takeover via \u0027sign_in\u0027 AJAX Action"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
    "assignerShortName": "Wordfence",
    "cveId": "CVE-2026-7520",
    "datePublished": "2026-08-05T07:39:23.697Z",
    "dateReserved": "2026-04-30T16:42:06.998Z",
    "dateUpdated": "2026-08-05T13:11:29.519Z",
    "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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.