Description
In the Linux kernel, the following vulnerability has been resolved:

usb: usbtmc: Flush anchored URBs in usbtmc_release

When calling usbtmc_release, pending anchored URBs must be flushed or
killed to prevent use-after-free errors (e.g. in the HCD giveback
path). Call usbtmc_draw_down() to allow anchored URBs to be completed.
Published: 2026-05-01
Score: 7.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

The usbtmc_release function in the Linux USB Test and Measurement Class driver fails to flush or kill pending anchored URBs. This omission creates a use‑after‑free condition that can corrupt kernel memory if a freed URB is later referenced during device teardown or the HCD giveback process. The flaw is a classic Use‑After‑Free (CWE‑416) and is also classified as Out‑of‑Band Notification of Resource Leak (CWE‑825) because anchored URBs are not completed before the device is released.

Affected Systems

The CPE list in the advisory lists affected kernels for the 7.0 release candidates from rc1 through rc6. Exact affected versions are not enumerated beyond those RCs, so any Linux kernel that contains the usbtmc driver before the commit that added the clean‑up call is potentially vulnerable. Consequently, systems running an unpatched 7.0 RC kernel or any earlier kernel that does not include the fix commit are at risk. The advisory does not explicitly confirm whether earlier stable releases are affected, so that information remains uncertain.

Risk and Exploitability

The CVSS score of 7.8 indicates medium‑high severity, while an EPSS score of <1% implies a very low exploitation probability. The vulnerability is not listed in the CISA KEV catalog. The likely attack vector is local device attachment, inferred from the fact that the issue is triggered when a USBTMC device is released. An attacker who can physically connect a malicious USBTMC device can exploit the flaw by provoking usbtmc_release, leaving an anchored URB in a freed memory context and potentially causing a kernel panic or memory corruption. Because the description specifies that the problem occurs during device teardown, it is reasonable to infer a local, hardware‑based exploitation path.

Generated by OpenCVE AI on May 8, 2026 at 21:09 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Apply a kernel update that includes the usbtmc_release fix commit.
  • If an immediate kernel upgrade is not possible, unload or disable the usbtmc module so the driver will not handle USBTMC devices.
  • Restrict USB device access on the system (for example, via udev rules or USB usage policies) to prevent unauthorized USBTMC devices from connecting.

Generated by OpenCVE AI on May 8, 2026 at 21:09 UTC.

Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-4561-1 linux-6.1 security update
Debian DSA Debian DSA DSA-6243-1 linux security update
History

Fri, 08 May 2026 18:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416
CPEs cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*

Sun, 03 May 2026 06:30:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Sat, 02 May 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-825
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate


Fri, 01 May 2026 14:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: usb: usbtmc: Flush anchored URBs in usbtmc_release When calling usbtmc_release, pending anchored URBs must be flushed or killed to prevent use-after-free errors (e.g. in the HCD giveback path). Call usbtmc_draw_down() to allow anchored URBs to be completed.
Title usb: usbtmc: Flush anchored URBs in usbtmc_release
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-05-11T22:15:14.753Z

Reserved: 2026-03-09T15:48:24.139Z

Link: CVE-2026-31758

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2026-05-01T15:16:38.807

Modified: 2026-05-08T18:23:22.020

Link: CVE-2026-31758

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-05-01T00:00:00Z

Links: CVE-2026-31758 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-05-08T21:15:05Z

Weaknesses