Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-02-03 08:44

Modified

2026-02-03 09:12

Summary

Mastodon vulnerable to Denial of Service from a single post (client/server)

Details

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing resource consumption. Depending on the number of poll options, an attacker can cause disproportionate resource usage in both Mastodon servers and clients, potentially causing Denial of Service either server-side or client-side. Mastodon versions v4.5.5, v4.4.12, v4.3.18 are patched.

JSON

To clipboard Create KEV Entry

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "mastodon",
        "purl": "pkg:bitnami/mastodon"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.3.18"
            },
            {
              "introduced": "4.4.0"
            },
            {
              "fixed": "4.4.12"
            },
            {
              "introduced": "4.5.0"
            },
            {
              "fixed": "4.5.5"
            }
          ],
          "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-2026-23962"
  ],
  "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 versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing resource consumption. Depending on the number of poll options, an attacker can cause disproportionate resource usage in both Mastodon servers and clients, potentially causing Denial of Service either server-side or client-side. Mastodon versions v4.5.5, v4.4.12, v4.3.18 are patched.",
  "id": "BIT-mastodon-2026-23962",
  "modified": "2026-02-03T09:12:55.720Z",
  "published": "2026-02-03T08:44:37.076Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/mastodon/mastodon/releases/tag/v4.3.18"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mastodon/mastodon/releases/tag/v4.4.12"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mastodon/mastodon/releases/tag/v4.5.5"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-gg8q-rcg7-p79g"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23962"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Mastodon vulnerable to Denial of Service from a single post (client/server)"
}

CVE-2026-23962 (GCVE-0-2026-23962)

Vulnerability from cvelistv5 – Published: 2026-01-22 01:51 – Updated: 2026-01-22 21:35

Title

Mastodon vulnerable to Denial of Service from a single post (client/server)

Summary

Severity ?

7.5 (High)


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

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

GitHub_M

References

URL

Tags

	https://github.com/mastodon/mastodon/security/adv…	x_refsource_CONFIRM
	https://github.com/mastodon/mastodon/releases/tag…	x_refsource_MISC
	https://github.com/mastodon/mastodon/releases/tag…	x_refsource_MISC
	https://github.com/mastodon/mastodon/releases/tag…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	mastodon	mastodon	Affected: < 4.3.18 Affected: >= 4.4.0, < 4.4.12 Affected: >= 4.5.0, < 4.5.5

Show details on NVD website

JSON

To clipboard Create KEV Entry

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-23962",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-22T21:34:54.544661Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-01-22T21:35:41.343Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "mastodon",
          "vendor": "mastodon",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.3.18"
            },
            {
              "status": "affected",
              "version": "\u003e= 4.4.0, \u003c 4.4.12"
            },
            {
              "status": "affected",
              "version": "\u003e= 4.5.0, \u003c 4.5.5"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mastodon is a free, open-source social network server based on ActivityPub. Mastodon versions before v4.3.18, v4.4.12, and v4.5.5 do not have a limit on the maximum number of poll options for remote posts, allowing attackers to create polls with a very large amount of options, greatly increasing resource consumption. Depending on the number of poll options, an attacker can cause disproportionate resource usage in both Mastodon servers and clients, potentially causing Denial of Service either server-side or client-side. Mastodon versions v4.5.5, v4.4.12, v4.3.18 are patched."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "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:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-22T01:51:37.430Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/mastodon/mastodon/security/advisories/GHSA-gg8q-rcg7-p79g",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-gg8q-rcg7-p79g"
        },
        {
          "name": "https://github.com/mastodon/mastodon/releases/tag/v4.3.18",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mastodon/mastodon/releases/tag/v4.3.18"
        },
        {
          "name": "https://github.com/mastodon/mastodon/releases/tag/v4.4.12",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mastodon/mastodon/releases/tag/v4.4.12"
        },
        {
          "name": "https://github.com/mastodon/mastodon/releases/tag/v4.5.5",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mastodon/mastodon/releases/tag/v4.5.5"
        }
      ],
      "source": {
        "advisory": "GHSA-gg8q-rcg7-p79g",
        "discovery": "UNKNOWN"
      },
      "title": "Mastodon vulnerable to Denial of Service from a single post (client/server)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-23962",
    "datePublished": "2026-01-22T01:51:37.430Z",
    "dateReserved": "2026-01-19T14:49:06.313Z",
    "dateUpdated": "2026-01-22T21:35:41.343Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

Vulnerability from bitnami_vulndb

CVE-2026-23962 (GCVE-0-2026-23962)

Tags

Sightings

Nomenclature