CVE-2025-39694

Full vulnerability record from the local CVENow database.
Description

In the Linux kernel, the following vulnerability has been resolved: s390/sclp: Fix SCCB present check Tracing code called by the SCLP interrupt handler contains early exits if the SCCB address associated with an interrupt is NULL. This check is performed after physical to virtual address translation. If the kernel identity mapping does not start at address zero, the resulting virtual address is never zero, so that the NULL checks won't work. Subsequently this may result in incorrect accesses to the first page of the identity mapping. Fix this by introducing a function that handles the NULL case before address translation.
Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-09-05 18:15:46.247000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
  "id": "CVE-2025-39694",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2025-09-05T18:15:46.247",
  "lastModified": "2026-10-19T21:10:00.160",
  "vulnStatus": "Modified",
  "cveTags": [],
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    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/sclp: Fix SCCB present check\n\nTracing code called by the SCLP interrupt handler contains early exits\nif the SCCB address associated with an interrupt is NULL. This check is\nperformed after physical to virtual address translation.\n\nIf the kernel identity mapping does not start at address zero, the\nresulting virtual address is never zero, so that the NULL checks won't\nwork. Subsequently this may result in incorrect accesses to the first\npage of the identity mapping.\n\nFix this by introducing a function that handles the NULL case before\naddress translation."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ns390/sclp: Corrección de la comprobación de presencia de SCCB\n\nEl código de rastreo llamado por el gestor de interrupciones SCLP contiene salidas tempranas si la dirección SCCB asociada a una interrupción es NULL. Esta comprobación se realiza después de la traducción de direcciones físicas a virtuales.\n\nSi el mapeo de identidad del kernel no comienza en la dirección cero, la dirección virtual resultante nunca es cero, por lo que las comprobaciones de NULL no funcionarán. Posteriormente, esto puede resultar en accesos incorrectos a la primera página del mapeo de identidad.\n\nSolucione esto introduciendo una función que maneje el caso NULL antes de la traducción de direcciones."
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