usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers() (CVE-2026-90023) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-90023

usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers()

Answer in brief

CVE-2026-90023 records a Unknown severity vulnerability in usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 16, 2026Updated Sep 16, 2026Source checked Sep 16, 2026First seen by HOL Sep 16, 2026Material review Sep 16, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=fe5a6c48fd954489f51aab151d5dad9254c76419 <9e8dd2a7a8ccbb756771ad985b0ad3387ed3c957 \|\| >=fe5a6c48fd954489f51aab151d5dad9254c76419 <b9b5b5df5b8dd3c1572ed267200276a44cc67d8e \|\| >=fe5a6c48fd954489f51aab151d5dad9254c76419 <2c0f5ca48674a5b5f9fa4a9c3325aa48053af0bc	9e8dd2a7a8ccbb756771ad985b0ad3387ed3c957, b9b5b5df5b8dd3c1572ed267200276a44cc67d8e, 2c0f5ca48674a5b5f9fa4a9c3325aa48053af0bc
Linux/Linuxgeneric	4.8	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 9e8dd2a7a8ccbb756771ad985b0ad3387ed3c957 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 16, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers() Previously fsg_num_buffers_validate() was removed as it was not necessary due to Kconfig setting the limits for n from 2 to 256 with default as 2. However, setting the page content in such a way that kstrtou8() reflects n value as either 0 or 1 bypasses these restrictions leading to a null pointer dereference if n is 0. Fix this by adding a check for n < 2 and returning -EINVAL if n is either 0 or 1 consistent with Kconfig logic.

Quoted source text, attributed separately from HOL analysis.