NVD / CVE Program· CNA Linux

CVE-2025-39721: crypto: qat - flush misc workqueue during device shutdown

Noroxi assessment

Priority: Monitor (action score 22/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.15% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Linux Linux 3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a, 5858448a6c65d8ee3f8600570d3ce19febcb33be, e59a52e429e13df3feb34f4853a8e36d121ed937.

Low priority for now. Upgrade to Linux Linux 3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a, 5858448a6c65d8ee3f8600570d3ce19febcb33be, e59a52e429e13df3feb34f4853a8e36d121ed937 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: crypto: qat - flush misc workqueue during device shutdown Repeated loading and unloading of a device specific QAT driver, for example qat_4xxx, in a tight loop can lead to a crash due to a use-after-free scenario. This occurs when a power management (PM) interrupt triggers just before the device-specific driver (e.g., qat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains loaded. Since the driver uses a shared workqueue (`qat_misc_wq`) across all devices and owned by intel_qat.ko, a deferred routine from the device-specific driver may still be pending in the queue. If this routine executes after the driver is unloaded, it can dereference freed memory, resulting in a page fault and kernel crash like the following: BUG: unable to handle page fault for address: ffa000002e50a01c #PF: supervisor read access in kernel mode RIP: 0010:pm_bh_handler+0x1d2/0x250 [intel_qat] Call Trace: pm_bh_handler+0x1d2/0x250 [intel_qat] process_one_work+0x171/0x340 worker_thread+0x277/0x3a0 kthread+0xf0/0x120 ret_from_fork+0x2d/0x50 To prevent this, flush the misc workqueue during device shutdown to ensure that all pending work items are completed before the driver is unloaded. Note: This approach may slightly increase shutdown latency if the workqueue contains jobs from other devices, but it ensures correctness and stability.

MediumCVSS 5.5 · v3.1—No exploit Fix available

BDU:2026-02859

Published: Sep 5, 2025
Updated: Nov 5, 2026
EPSS: 0.1% · 4th percentile
CWE: CWE-416

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 22 / 40 · 5.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

linux linux kernel5.18 and later · before 6.6.103
linux linux kernel6.7 and later · before 6.12.44
linux linux kernel6.13 and later · before 6.16.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

Linux Linux
- 5.18affected
- e5745f34113b758b45d134dec04a7df94dc67131 and later · before fa4c14a82747886d333d8baef0d26da86ba1ccf7affected · git
- e5745f34113b758b45d134dec04a7df94dc67131 and later · before 5858448a6c65d8ee3f8600570d3ce19febcb33beaffected · git
- e5745f34113b758b45d134dec04a7df94dc67131 and later · before fe546f5c50fc474daca6bee72caa7ab68a74c33daffected · git
- e5745f34113b758b45d134dec04a7df94dc67131 and later · before e59a52e429e13df3feb34f4853a8e36d121ed937affected · git
- e5745f34113b758b45d134dec04a7df94dc67131 and later · before 3d4df408ba9bad2b205c7fb8afc1836a6a4ca88aaffected · git
- before 5.18not affected · semver
- 6.1.162 and later · up to and including 6.1.*not affected · semver
- 6.6.103 and later · up to and including 6.6.*not affected · semver
- 6.12.44 and later · up to and including 6.12.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.162-1	6.1.162-1
Debian:13	linux	before 6.12.48-1	6.12.48-1
Debian:14	linux	before 6.16.5-1	6.16.5-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
90Now
CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
89Now
CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
85Now

Published before and after this one in the same product

← EarlierCVE-2025-39719Sep 5, 2025 · iio: imu: bno055: fix OOB access of hw_xlate array
28Monitor
← EarlierCVE-2025-39720Sep 5, 2025 · ksmbd: fix refcount leak causing resource not released
22Monitor
Later →CVE-2025-39722Sep 5, 2025 · crypto: caam - Prevent crash on suspend with iMX8QM / iMX8ULP
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Linux Linux	3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a	Vendor (CNA)
Linux Linux	5858448a6c65d8ee3f8600570d3ce19febcb33be	Vendor (CNA)
Linux Linux	e59a52e429e13df3feb34f4853a8e36d121ed937	Vendor (CNA)
Linux Linux	fa4c14a82747886d333d8baef0d26da86ba1ccf7	Vendor (CNA)
Linux Linux	fe546f5c50fc474daca6bee72caa7ab68a74c33d	Vendor (CNA)
debian:linux	6.1.162-1 · Debian:12	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

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

nvd-primary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

SSVC exploitation— → noneNov 5, 2026, 11:07 PM UTC
Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

For records you follow, these changes also arrive as notifications. →

References

git.kernel.org/stable/c/3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a

Show all references (6 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

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