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CVE-2026-23437

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect late read accesses to the hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. This is not proper, a conversion from a ref to a locked netdev must include a liveness check (a check if the netdev hasn't been unregistered already). Fix the read cases (those under RCU). Writes needs a separate change to protect from creating the hierarchy after flush has already run.

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-03 16:16:25.400000
Last modified
2026-10-19 19:17:48.103000
View original CVE JSON
{
  "id": "CVE-2026-23437",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-04-03T16:16:25.400",
  "lastModified": "2026-10-19T19:17:48.103",
  "vulnStatus": "Modified",
  "cveTags": [],
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    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: shaper: protect late read accesses to the hierarchy\n\nWe look up a netdev during prep of Netlink ops (pre- callbacks)\nand take a ref to it. Then later in the body of the callback\nwe take its lock or RCU which are the actual protections.\n\nThis is not proper, a conversion from a ref to a locked netdev\nmust include a liveness check (a check if the netdev hasn't been\nunregistered already). Fix the read cases (those under RCU).\nWrites needs a separate change to protect from creating the\nhierarchy after flush has already run."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet: shaper: proteger los accesos de lectura tardíos a la jerarquía\n\nBuscamos un netdev durante la preparación de las operaciones de Netlink (pre-callbacks) y tomamos una referencia a él. Luego, más tarde, en el cuerpo del callback, tomamos su bloqueo o RCU, que son las protecciones reales.\n\nEsto no es adecuado; una conversión de una referencia a un netdev bloqueado debe incluir una comprobación de actividad (una comprobación de si el netdev no ha sido ya desregistrado). Corregir los casos de lectura (aquellos bajo RCU). Las escrituras necesitan un cambio separado para proteger de la creación de la jerarquía después de que el vaciado ya se haya ejecutado."
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