debugfs: Fix lockdown check for mmap_prepare

Answer in brief

CVE-2026-89745 records a Unknown severity vulnerability in debugfs: Fix lockdown check for mmap_prepare. 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 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 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	>=651fdda8406d42a5004c5c79f269540a85d6a1ab <e7f6a6b5741d16fdac7adaecbe0fa52ae756f208 \|\| >=651fdda8406d42a5004c5c79f269540a85d6a1ab <f81808de37338aac8e167f99bfae647b1b835c70	e7f6a6b5741d16fdac7adaecbe0fa52ae756f208, f81808de37338aac8e167f99bfae647b1b835c70
Linux/Linuxgeneric	6.19	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to e7f6a6b5741d16fdac7adaecbe0fa52ae756f208 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: debugfs: Fix lockdown check for mmap_prepare Commit 651fdda8406d ("relay: update relay to use mmap_prepare") changed the `mmap` file operation to `mmap_prepare` for relayfs, but the lockdown check in debugfs was not updated accordingly. This prevents debugfs from being locked down when the kernel is in integrity mode if a file uses `mmap_prepare` but not `mmap`. Since the conversion to `mmap_prepare` across the kernel is not yet complete, update the lockdown check to look for both `mmap` and `mmap_prepare` to ensure comprehensive coverage.

Quoted source text, attributed separately from HOL analysis.