High 7.8Published Sep 23, 2025

CVE-2025-39871dmaengine: idxd: Remove improper idxd_free

Updated under an hour ago (Oct 28, 2026, 5:10 AM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Remove improper idxd_free The call to idxd_free() introduces a duplicate put_device() leading to a reference count underflow: refcount_t: underflow; use-after-free. WARNING: CPU: 15 PID: 4428 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110 ... Call Trace: <TASK> idxd_remove+0xe4/0x120 [idxd] pci_device_remove+0x3f/0xb0 device_release_driver_internal+0x197/0x200 driver_detach+0x48/0x90 bus_remove_driver+0x74/0xf0 pci_unregister_driver+0x2e/0xb0 idxd_exit_module+0x34/0x7a0 [idxd] __do_sys_delete_module.constprop.0+0x183/0x280 do_syscall_64+0x54/0xd70 entry_SYSCALL_64_after_hwframe+0x76/0x7e The idxd_unregister_devices() which is invoked at the very beginning of idxd_remove(), already takes care of the necessary put_device() through the following call path: idxd_unregister_devices() -> device_unregister() -> put_device() In addition, when CONFIG_DEBUG_KOBJECT_RELEASE is enabled, put_device() may trigger asynchronous cleanup via schedule_delayed_work(). If idxd_free() is called immediately after, it can result in a use-after-free. Remove the improper idxd_free() to avoid both the refcount underflow and potential memory corruption during module unload.

CVSS: 7.8 HIGH (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 14, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 68ac5a01f635b3791196fd1c39bc48497252c36f before 24414bbcb37e1af95190af36c21ae51d497e1a9e; from d2d05fd0fc95c4defed6f7b87550e20e8baa1d97 before 0e95ee7f532b21206fe3f1c4054002b0d21e3b9c; from 21f9f5cd9a0c75084d4369ba0b8c4f695c41dea7 before dd7a7e43269711d757fc260b0bbdf7138f75de11; from d5449ff1b04dfe9ed8e455769aa01e4c2ccf6805 before da4fbc1488a4cec6748da685181ee4449a878dac; from d5449ff1b04dfe9ed8e455769aa01e4c2ccf6805 before f41c538881eec4dcf5961a242097d447f848cda6; 2b7a961cea0e5b65afda911f76d14fec5c98d024; from 6.1.140 before 6.1.160; from 6.6.92 before 6.6.107; and 2 more ranges	CNA record
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.6	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.6	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.6	CISA ADP
linux linux_kernel linux:linux_kernel	from 6.1.140 before 6.2; from 6.6.92 before 6.6.107; from 6.12.30 before 6.12.48; from 6.14.8 before 6.15; from 6.15.1 before 6.16.8; 6.15; 6.15; 6.17; and 4 more ranges	NVD

References

References

https://git.kernel.org/stable/c/24414bbcb37e1af95190af36c21ae51d497e1a9e
https://git.kernel.org/stable/c/0e95ee7f532b21206fe3f1c4054002b0d21e3b9c	patch
https://git.kernel.org/stable/c/dd7a7e43269711d757fc260b0bbdf7138f75de11	patch
https://git.kernel.org/stable/c/da4fbc1488a4cec6748da685181ee4449a878dac	patch
https://git.kernel.org/stable/c/f41c538881eec4dcf5961a242097d447f848cda6	patch
https://cert-portal.siemens.com/productcert/html/ssa-019113.html
https://cert-portal.siemens.com/productcert/html/ssa-457936.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.