Linux Kernel up to 6.12.45/6.16.5/6.17-rc4 ice ice_ll_ts_intr use after free

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.45/6.16.5/6.17-rc4. Affected by this issue is the function ice_ll_ts_intr of the component ice. This manipulation causes use after free. This vulnerability is handled as CVE-2025-39854. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.12.45/6.16.5/6.17-rc4. It has been declared as critical. Affected by this vulnerability is the function ice_ll_ts_intr of the component ice. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ice: fix NULL access of tx->in_use in ice_ll_ts_intr Recent versions of the E810 firmware have support for an extra interrupt to handle report of the "low latency" Tx timestamps coming from the specialized low latency firmware interface. Instead of polling the registers, software can wait until the low latency interrupt is fired. This logic makes use of the Tx timestamp tracking structure, ice_ptp_tx, as it uses the same "ready" bitmap to track which Tx timestamps complete. Unfortunately, the ice_ll_ts_intr() function does not check if the tracker is initialized before its first access. This results in NULL dereference or use-after-free bugs similar to the issues fixed in the ice_ptp_ts_irq() function. Fix this by only checking the in_use bitmap (and other fields) if the tracker is marked as initialized. The reset flow will clear the init field under lock before it tears the tracker down, thus preventing any use-after-free or NULL access.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-39854 since 04/16/2025. The exploitation appears to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/22/2025).

The vulnerability scanner Nessus provides a plugin with the ID 265462 (Linux Distros Unpatched Vulnerability : CVE-2025-39854), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.46, 6.16.6 or 6.17-rc5 eliminates this vulnerability. Applying the patch 2cde98a02da958357fe240a6ba269b69d913b6ba/923c267bdbb64f65bc1149d184efcf8b047d7d64/f6486338fde3f04ed0ec59fe67a69a208c32734f 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 (265462) and CERT Bund (WID-SEC-2025-2099). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM QRadar SIEM
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.16.4
• 6.16.5
• 6.17-rc1
• 6.17-rc2
• 6.17-rc3
• 6.17-rc4

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

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