Linux Kernel up to 6.16.3/6.17-rc2 riscv_iommu_pte_fetch null pointer dereference

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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.16.3/6.17-rc2 and classified as critical. This affects the function riscv_iommu_pte_fetch. This manipulation causes null pointer dereference. This vulnerability is registered as CVE-2025-39699. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.16.3/6.17-rc2. Affected by this vulnerability is the function riscv_iommu_pte_fetch. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

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.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2025-39699 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 261602 (Linux Distros Unpatched Vulnerability : CVE-2025-39699), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.16.4 or 6.17-rc3 eliminates this vulnerability. Applying the patch 220c491490255b656672bb572b18460cd9155926/99d4d1a070870aa08163af8ce0522992b7f35d8c is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (261602) and CERT Bund (WID-SEC-2025-1988). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • NetApp FAS
  • NetApp AFF
  • NetApp ActiveIQ Unified Manager
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • Microsoft Azure
  • Dell Secure Connect Gateway
  • IBM QRadar SIEM
  • IBM Security Verify Access
  • Dell NetWorker

Productinfo

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 261602
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39699

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.16.4/6.17-rc3
Patch: 220c491490255b656672bb572b18460cd9155926/99d4d1a070870aa08163af8ce0522992b7f35d8c

Timelineinfo

04/16/2025 CVE reserved
09/05/2025 +142 days Advisory disclosed
09/05/2025 +0 days VulDB entry created
02/09/2026 +157 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39699 (🔒)
GCVE (CVE): GCVE-0-2025-39699
GCVE (VulDB): GCVE-100-322885
CERT Bund: WID-SEC-2025-1988 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 09/05/2025 21:43
Updated: 02/09/2026 18:22
Changes: 09/05/2025 21:43 (58), 09/07/2025 13:19 (2), 11/06/2025 20:31 (7), 11/26/2025 16:04 (10), 11/27/2025 19:32 (1), 01/03/2026 13:29 (1), 01/05/2026 12:21 (1), 02/09/2026 18:22 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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