CVE-2026-68300

Estado: RecibidaCrítica (9.8)—

In the Linux kernel, the following vulnerability has been resolved:

sctp: auth: verify auth requirement when auth_chunk is NULL

sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when:

Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally.

Detalles técnicos trazas, registros y código del informe original

1. skb_clone() failed in the BH receive path, leaving auth_chunk
   NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new
   connections, so the early sctp_auth_recv_cid() check cannot
   catch this.

2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never
   called and auth_chunk remains NULL.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.59%
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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1499.004 Application or System Exploitationimpact75 %
Impacto secundarioT1565.002 Transmitted Data Manipulationimpact70 %

Vulnerabilidad remota en kernel Linux sin autenticación (AV:N/PR:N/UI:N) que permite bypass de autenticación SCTP. Explotable remotamente: T1190. Impactos: DoS por dropping de paquetes legítimos (T1499.004) y corrupción de integridad por aceptación de tráfico no autenticado (T1565.002).

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

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Encrypt Sensitive Information

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Linux — Linux Kernel^AI

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2026-68300",
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        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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          "version": "3.1",
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          "baseSeverity": "CRITICAL",
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    }
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  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: auth: verify auth requirement when auth_chunk is NULL\n\nsctp_auth_chunk_verify() returns true unconditionally when\nchunk->auth_chunk is NULL, silently skipping authentication.\nThis is incorrect when:\n\n1. skb_clone() failed in the BH receive path, leaving auth_chunk\n   NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new\n   connections, so the early sctp_auth_recv_cid() check cannot\n   catch this.\n\n2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never\n   called and auth_chunk remains NULL.\n\nFix by checking sctp_auth_recv_cid() when auth_chunk is NULL:\nif authentication is required, return false to drop the chunk;\notherwise continue normally."
    }
  ],
  "lastModified": "2026-08-19T17:20:41.187",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}