CVE-2021-30478
Estado: ModificadaMedia (4.3)—
An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the can_forge_sender permission (previously is_api_super_user) resulted in users with this permission being able to send messages appearing as if sent by a system bot, including to other organizations hosted by the same Zulip installation.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- Puntuación base: 4.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.57%
- Percentil entre todas las CVEs puntuadas: 46
- 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).
Tecnologías afectadas (1)
CWE
- CWE-269
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-30478",
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"vectorString": "AV:N/AC:L/Au:S/C:N/I:P/A:N",
"authentication": "SINGLE",
"integrityImpact": "PARTIAL",
"accessComplexity": "LOW",
"availabilityImpact": "NONE",
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"integrityImpact": "LOW",
"userInteraction": "NONE",
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"availabilityImpact": "NONE",
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"affected": [
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"affectedData": [
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"published": "2021-04-15T00:15:13.107",
"references": [
{
"url": "https://blog.zulip.com/2021/04/14/zulip-server-3-4/",
"tags": [
"Release Notes",
"Vendor Advisory"
],
"source": "cve@mitre.org"
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{
"url": "https://blog.zulip.com/2021/04/14/zulip-server-3-4/",
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"description": [
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"value": "CWE-269"
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"lang": "en",
"value": "An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the can_forge_sender permission (previously is_api_super_user) resulted in users with this permission being able to send messages appearing as if sent by a system bot, including to other organizations hosted by the same Zulip installation."
},
{
"lang": "es",
"value": "Se detectó un problema en Zulip Server versiones anteriores a 3.4. Un bug en la implementación del permiso can_forge_sender (anteriormente es_api_super_user) hizo a unos usuarios con este permiso pudieran enviar mensajes que parecían enviados por un bot del sistema, inclusive a otras organizaciones alojadas por la misma instalación de Zulip"
}
],
"lastModified": "2026-06-17T03:50:18.970",
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