Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2025-08-08 05:54

Modified

2026-09-08 08:34

Summary

Mastodon e‑mail throttle misconfiguration allows unlimited email confirmations against unconfirmed emails

Details

Mastodon is a free, open-source social network server based on ActivityPub Mastodon which facilitates LDAP configuration for authentication. In versions 3.1.5 through 4.2.24, 4.3.0 through 4.3.11 and 4.4.0 through 4.4.3, Mastodon's rate-limiting system has a critical configuration error where the email-based throttle for confirmation emails incorrectly checks the password reset path instead of the confirmation path, effectively disabling per-email limits for confirmation requests. This allows attackers to bypass rate limits by rotating IP addresses and send unlimited confirmation emails to any email address, as only a weak IP-based throttle (25 requests per 5 minutes) remains active. The vulnerability enables denial-of-service attacks that can overwhelm mail queues and facilitate user harassment through confirmation email spam. This is fixed in versions 4.2.24, 4.3.11 and 4.4.3.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "mastodon",
        "purl": "pkg:bitnami/mastodon"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.1.5"
            },
            {
              "fixed": "4.2.24"
            },
            {
              "introduced": "4.3.0"
            },
            {
              "fixed": "4.3.11"
            },
            {
              "introduced": "4.4.0"
            },
            {
              "fixed": "4.4.3"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-54879"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "Mastodon is a free, open-source social network server based on ActivityPub Mastodon which facilitates LDAP configuration for authentication. In versions 3.1.5 through 4.2.24, 4.3.0 through 4.3.11 and 4.4.0 through 4.4.3, Mastodon\u0027s rate-limiting system has a critical configuration error where the email-based throttle for confirmation emails incorrectly checks the password reset path instead of the confirmation path, effectively disabling per-email limits for confirmation requests. This allows attackers to bypass rate limits by rotating IP addresses and send unlimited confirmation emails to any email address, as only a weak IP-based throttle (25 requests per 5 minutes) remains active. The vulnerability enables denial-of-service attacks that can overwhelm mail queues and facilitate user harassment through confirmation email spam. This is fixed in versions 4.2.24, 4.3.11 and 4.4.3.",
  "id": "BIT-mastodon-2025-54879",
  "modified": "2026-09-08T08:34:36.952Z",
  "published": "2025-08-08T05:54:51.134Z",
  "references": [
    {
      "type": "FIX",
      "url": "https://github.com/mastodon/mastodon/commit/e2592419d93fb41be03c2f3ff6a122fecb0e0952"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/mastodon/mastodon/releases/tag/v4.4.3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-84ch-6436-c7mg"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54879"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Mastodon e\u2011mail throttle misconfiguration allows unlimited email confirmations against unconfirmed emails"
}

CVE-2025-54879 (GCVE-0-2025-54879)

Vulnerability from cvelistv5 – Published: 2025-08-05 23:39 – Updated: 2025-08-06 20:32

Title

Mastodon e‑mail throttle misconfiguration allows unlimited email confirmations against unconfirmed emails

Summary

Severity

5.3 (Medium)


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

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-08-06 20:32 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

GitHub_M mitre root Scorecard

References

3 references

URL	Tags
https://github.com/mastodon/mastodon/security/adv…	x_refsource_CONFIRM
https://github.com/mastodon/mastodon/commit/e2592…	x_refsource_MISC
https://github.com/mastodon/mastodon/releases/tag…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
mastodon	mastodon	Affected: >= 3.1.5, < 4.2.24 Affected: >= 4.3.0, < 4.3.11 Affected: >= 4.4.0, < 4.4.3

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-54879",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-08-06T20:32:42.219873Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-08-06T20:32:56.740Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-84ch-6436-c7mg"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "mastodon",
          "vendor": "mastodon",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.1.5, \u003c 4.2.24"
            },
            {
              "status": "affected",
              "version": "\u003e= 4.3.0, \u003c 4.3.11"
            },
            {
              "status": "affected",
              "version": "\u003e= 4.4.0, \u003c 4.4.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mastodon is a free, open-source social network server based on ActivityPub Mastodon which facilitates LDAP configuration for authentication. In versions 3.1.5 through 4.2.24, 4.3.0 through 4.3.11 and 4.4.0 through 4.4.3, Mastodon\u0027s rate-limiting system has a critical configuration error where the email-based throttle for confirmation emails incorrectly checks the password reset path instead of the confirmation path, effectively disabling per-email limits for confirmation requests. This allows attackers to bypass rate limits by rotating IP addresses and send unlimited confirmation emails to any email address, as only a weak IP-based throttle (25 requests per 5 minutes) remains active. The vulnerability enables denial-of-service attacks that can overwhelm mail queues and facilitate user harassment through confirmation email spam. This is fixed in versions 4.2.24, 4.3.11 and 4.4.3."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-08-05T23:39:59.130Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/mastodon/mastodon/security/advisories/GHSA-84ch-6436-c7mg",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-84ch-6436-c7mg"
        },
        {
          "name": "https://github.com/mastodon/mastodon/commit/e2592419d93fb41be03c2f3ff6a122fecb0e0952",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mastodon/mastodon/commit/e2592419d93fb41be03c2f3ff6a122fecb0e0952"
        },
        {
          "name": "https://github.com/mastodon/mastodon/releases/tag/v4.4.3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mastodon/mastodon/releases/tag/v4.4.3"
        }
      ],
      "source": {
        "advisory": "GHSA-84ch-6436-c7mg",
        "discovery": "UNKNOWN"
      },
      "title": "Mastodon e\u2011mail throttle misconfiguration allows unlimited email confirmations against unconfirmed emails"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2025-54879",
    "datePublished": "2025-08-05T23:39:59.130Z",
    "dateReserved": "2025-07-31T17:23:33.475Z",
    "dateUpdated": "2025-08-06T20:32:56.740Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

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.

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.

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Vulnerability from bitnami_vulndb

CVE-2025-54879 (GCVE-0-2025-54879)

Tags

Sightings

Nomenclature

Related by attack behaviour