CVE-2025-39699: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: iommu/riscv: prevent NULL deref in iova_to_phys The riscv_iommu_pte_fetch() function returns either NULL for unmapped/never-mapped iova, or a valid leaf pte pointer that requires no further validation. riscv_iommu_iova_to_phys() failed to handle NULL returns. Prevent null pointer dereference in riscv_iommu_iova_to_phys(), and remove the pte validation.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	6.13 — 6.16.4
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/220c491490255b656672bb572b18460cd9155926 https://git.kernel.org/stable/c/99d4d1a070870aa08163af8ce0522992b7f35d8c

Frequently Asked Questions

What is CVE-2025-39699? +

In the Linux kernel, the following vulnerability has been resolved: iommu/riscv: prevent NULL deref in iova_to_phys The riscv_iommu_pte_fetch() function returns either NULL for unmapped/never-mapped iova, or a valid leaf pte pointer that requires no further validation. riscv_iommu_iova_to_phys() failed to handle NULL returns. Prevent null pointer dereference in riscv_iommu_iova_to_phys(), and remove the pte validation. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-39699? +

CVE-2025-39699 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-39699? +

CVE-2025-39699 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-39699? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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