CVE-2026-99242 Exposición de información por carrera entre fallocate y lecturas mmap en NTFS

Afectados

• Linux

  desde 495e90fa334828d4119061e2726af51d0a0fb4ed hasta antes de 7dd1c2fec6ebdd1a88a02cb58ff515a258eeb327desde 495e90fa334828d4119061e2726af51d0a0fb4ed hasta antes de 67aded1da114dc44808315f249bd9e7e440f799d

• Linux

  7.1

Qué hacer

1. Verificá si usás Linux y en qué versión.
2. Actualizá a la versión corregida que indique el fabricante en su aviso o aplicá su mitigación.
3. Revisá registros y accesos de los sistemas expuestos para descartar un uso previo.

Calculadora CVSS

Esta vulnerabilidad todavía no tiene vector CVSS publicado.

Descripción original

In the Linux kernel, the following vulnerability has been resolved: ntfs: fix race between fallocate and mmap reads The fallocate implementation only takes invalidate_lock for punch hole, collapse range, and insert range operations. For standard allocation modes (mode == 0, FALLOC_FL_KEEP_SIZE), the lock is not held. During ntfs_attr_fallocate(), new clusters are mapped to the runlist via ntfs_attr_map_cluster() before being zeroed by ntfs_dio_zero_range(). This creates a window where concurrent mmap page faults can read uninitialized disk data. Since mmap uses filemap_fault() which takes invalidate_lock in shared mode, it can fault in pages during this window and expose old disk contents to userspace. This is an information leak and data integrity issue. Fix by taking invalidate_lock for all fallocate operations, not just for punch/collapse/insert modes. This prevents concurrent page faults from accessing unzeroed clusters during the allocation window.

Referencias (2)

• git.kernel.org/stable/c/7dd1c2fec6ebdd1a88a02cb58ff515a258eeb327
• git.kernel.org/stable/c/67aded1da114dc44808315f249bd9e7e440f799d

Resumen traducido automáticamente de la descripción original. Fuente: Nureq Monitor. Cómo funciona.