CVE-2026-23962
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.55%
- Percentil entre todas las CVEs puntuadas: 44
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1499.004Application or System Exploitationimpact90 %
Vector AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). CWE-770 y descripción sustentan DoS por consumo de recursos mediante polls con opciones masivas (T1499.004).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-770
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-23962",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-23962",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-01-22T21:34:54.544661Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "mastodon",
"product": "mastodon",
"versions": [
{
"status": "affected",
"version": "< 4.3.18"
},
{
"status": "affected",
"version": ">= 4.4.0, < 4.4.12"
},
{
"status": "affected",
"version": ">= 4.5.0, < 4.5.5"
}
]
}
]
}
],
"published": "2026-01-22T03:15:46.400",
"references": [
{
"url": "https://github.com/mastodon/mastodon/releases/tag/v4.3.18",
"tags": [
"Release Notes"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/mastodon/mastodon/releases/tag/v4.4.12",
"tags": [
"Release Notes"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/mastodon/mastodon/releases/tag/v4.5.5",
"tags": [
"Release Notes"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/mastodon/mastodon/security/advisories/GHSA-gg8q-rcg7-p79g",
"tags": [
"Vendor Advisory"
],
"source": "security-advisories@github.com"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-770"
}
]
}
],
"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."
},
{
"lang": "es",
"value": "Mastodon es un servidor de red social gratuito y de código abierto basado en ActivityPub. Las versiones de Mastodon anteriores a la v4.3.18, v4.4.12 y v4.5.5 no tienen un límite en el número máximo de opciones de encuesta para publicaciones remotas, lo que permite a los atacantes crear encuestas con una cantidad muy grande de opciones, aumentando considerablemente el consumo de recursos. Dependiendo del número de opciones de encuesta, un atacante puede causar un uso desproporcionado de recursos tanto en los servidores como en los clientes de Mastodon, lo que podría causar una denegación de servicio ya sea del lado del servidor o del lado del cliente. Las versiones de Mastodon v4.5.5, v4.4.12, v4.3.18 están parcheadas."
}
],
"lastModified": "2026-06-17T10:22:21.643",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "0ADDA491-E534-4DFB-856F-9D07F38F3A92",
"versionEndExcluding": "4.3.18"
},
{
"criteria": "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9BAA2A25-EE70-4B9F-8848-2CCE9C243077",
"versionEndExcluding": "4.4.12",
"versionStartIncluding": "4.4.0"
},
{
"criteria": "cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "71845808-53CF-46D1-9A12-F14F1BAED488",
"versionEndExcluding": "4.5.5",
"versionStartIncluding": "4.5.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}