NVD / CVE Program· CNA Linux

CVE-2025-21923: HID: hid-steam: Fix use-after-free when detaching device

Noroxi assessment

Priority: Monitor (action score 31/100)

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: 0.20% (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 026714ec7546de741826324a6a1914c91024d06c, 6.12.19, 6.13.7; azl3 kernel 6.6.82.1-1 on Azure Linux 3.0 6.6.85.1-2; azl3 kernel 6.6.85.1-2 on Azure Linux 3.0 6.6.85.1-2.

Low priority for now. Upgrade to Linux Linux 026714ec7546de741826324a6a1914c91024d06c, 6.12.19, 6.13.7; azl3 kernel 6.6.82.1-1 on Azure Linux 3.0 6.6.85.1-2; azl3 kernel 6.6.85.1-2 on Azure Linux 3.0 6.6.85.1-2 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: HID: hid-steam: Fix use-after-free when detaching device When a hid-steam device is removed it must clean up the client_hdev used for intercepting hidraw access. This can lead to scheduling deferred work to reattach the input device. Though the cleanup cancels the deferred work, this was done before the client_hdev itself is cleaned up, so it gets rescheduled. This patch fixes the ordering to make sure the deferred work is properly canceled.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

BDU:2025-05643

Published: Apr 1, 2025
Updated: Aug 5, 2026
EPSS: 0.2% · 11th percentile
CWE: CWE-416

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 7.8
CNA · Linux: 7.8; agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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

If any of these changes, we'll tell you in the daily email digest.

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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 kernel6.6.79 and later · before 6.6.83
linux linux kernel6.12.16 and later · before 6.12.19
linux linux kernel6.13.4 and later · before 6.13.7

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
- e1147961b2145fa61c3078a4a797d9576cde91ab and later · before 026714ec7546de741826324a6a1914c91024d06caffected · git
- 3e38cbbfa0a128a9d64773240a9eb3bc7bae3b1a and later · before a899adf7063c6745aaff1ec869f3c7f6329ed0a1affected · git
- 053fa3888d2a957f4db26c05e503f4c6b9570a30 and later · before ea3f18d2f02629653b7bfe42607737ccd1343e54affected · git
- 79504249d7e27cad4a3eeb9afc6386e418728ce0 and later · before e53fc232a65f7488ab75d03a5b95f06aaada7262affected · git
- 6.6.79 and later · before 6.6.83affected · semver
- 6.12.16 and later · before 6.12.19affected · semver
- 6.13.4 and later · before 6.13.7affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:13	linux	before 6.12.19-1	6.12.19-1

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-2025-21920Apr 1, 2025 · vlan: enforce underlying device type
28Monitor
← EarlierCVE-2025-21922Apr 1, 2025 · ppp: Fix KMSAN uninit-value warning with bpf
22Monitor
Later →CVE-2025-21928Apr 1, 2025 · HID: intel-ish-hid: Fix use-after-free issue in ishtp_hid_remove()
31Monitor

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	026714ec7546de741826324a6a1914c91024d06c	Vendor (CNA)
Linux Linux	6.12.19	Vendor (CNA)
Linux Linux	6.13.7	Vendor (CNA)
Linux Linux	6.6.83	Vendor (CNA)
Linux Linux	a899adf7063c6745aaff1ec869f3c7f6329ed0a1	Vendor (CNA)
Linux Linux	e53fc232a65f7488ab75d03a5b95f06aaada7262	Vendor (CNA)
Linux Linux	ea3f18d2f02629653b7bfe42607737ccd1343e54	Vendor (CNA)
azl3 kernel 6.6.82.1-1 on Azure Linux 3.0	6.6.85.1-2 · CBL-Mariner Releases	Microsoft (MSRC)
azl3 kernel 6.6.85.1-2 on Azure Linux 3.0	6.6.85.1-2 · CBL-Mariner Releases	Microsoft (MSRC)
debian:linux	6.12.19-1 · Debian:13	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: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

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

Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

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

References

git.kernel.org/stable/c/026714ec7546de741826324a6a1914c91024d06c

Show all references (3 more)

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

All records