PT-2025-51564 · Git+3 · Kernel+91

Published 2025-12-16 · Updated 2025-12-17 · CVE-2025-40348

Positive Technologies (AI Summary)

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A race condition exists within the kernel's slab allocator, specifically in the alloc slab obj exts() function. When multiple threads concurrently attempt to allocate object extensions, a failure in one thread can overwrite the valid slab->obj exts pointer allocated by another thread with OBJEXTS ALLOC FAIL. This can lead to a subsequent null pointer dereference in the thread that expected a valid pointer. The issue is addressed by atomically updating slab->obj exts using a compare-and-swap (cmpxchg()) operation to prevent overrides by competing threads.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Related Identifiers

CVE-2025-40348

Affected Products

Kernel

Linux

Linux-Allwinner-5.19

Linux-Aws

Linux-Aws-5.0

Linux-Aws-5.11

Linux-Aws-5.13

Linux-Aws-5.19

Linux-Aws-5.3

Linux-Aws-5.8

Linux-Aws-6.2

Linux-Aws-6.5

Linux-Aws-Fips

Linux-Azure

Linux-Azure-5.11

Linux-Azure-5.13

Linux-Azure-5.19

Linux-Azure-5.3

Linux-Azure-5.8

Linux-Azure-6.11

Linux-Azure-6.2

Linux-Azure-6.5

Linux-Azure-Edge

Linux-Azure-Fde

Linux-Azure-Fde-5.19

Linux-Azure-Fde-6.2

Linux-Fips

Linux-Gcp

Linux-Gcp-5.11

Linux-Gcp-5.13

Linux-Gcp-5.19

Linux-Gcp-5.3

Linux-Gcp-5.8

Linux-Gcp-6.11

Linux-Gcp-6.2

Linux-Gcp-6.5

Linux-Gke

Linux-Gke-4.15

Linux-Gkeop-5.15

Linux-Gke-5.4

Linux-Gkeop

Linux-Hwe

Linux-Hwe-5.11

Linux-Hwe-5.13

Linux-Hwe-5.19

Linux-Hwe-5.8

Linux-Hwe-6.11

Linux-Hwe-6.2

Linux-Hwe-6.5

Linux-Hwe-Edge

Linux-Intel-5.13

Linux-Intel-Iot-Realtime

Linux-Lowlatency-Hwe-5.19

Linux-Lowlatency-Hwe-6.11

Linux-Lowlatency-Hwe-6.2

Linux-Lowlatency-Hwe-6.5

Linux-Lts

Linux-Nvidia-6.11

Linux-Nvidia-6.2

Linux-Nvidia-6.5

Linux-Oem

Linux-Oem-5.10

Linux-Oem-5.13

Linux-Oem-5.14

Linux-Oem-5.17

Linux-Oem-5.6

Linux-Oem-6.0

Linux-Oem-6.1

Linux-Oem-6.11

Linux-Oem-6.5

Linux-Oem-6.8

Linux-Oracle

Linux-Oracle-5.0

Linux-Oracle-5.11

Linux-Oracle-5.13

Linux-Oracle-5.3

Linux-Oracle-5.8

Linux-Oracle-6.5

Linux-Raspi

Linux-Raspi-Realtime

Linux-Raspi2

Linux-Realtime

Linux-Riscv

Linux-Riscv-5.11

Linux-Riscv-5.19

Linux-Riscv-5.8

Linux-Riscv-6.14

Linux-Riscv-6.5

Linux-Starfive-5.19

Linux-Starfive-6.2

Linux-Starfive-6.5

Linux-Xilinx

References · 14

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40348.json · Exploit
• https://cve.org/CVERecord?id=CVE-2025-40348 · Security Note
• https://osv.dev/vulnerability/BELL-CVE-2025-40348 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2025-40348 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-40348 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2025-40348 · Vendor Advisory
• https://linux.oracle.com/errata/ELSA-2026-50006.html · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-40348 · Vendor Advisory
• https://git.kernel.org/stable/c/6ed8bfd24ce1cb31742b09a3eb557cd008533eec · Note
• https://git.kernel.org/stable/c/c7af5300d78460fc5037ddc77113ba3dbfe77dc0 · Note
• https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git · Note
• https://git.kernel.org/stable/c/7c34feda6a9a203c9744281f1b6671b7dad2012d · Note
• https://git.kernel.org/linus/6ed8bfd24ce1cb31742b09a3eb557cd008533eec · Note
• https://docs.bell-sw.com/security/cves/CVE-2025-40348 · Note