liveupdate: Reference count incoming FLB data

Answer in brief

CVE-2026-80642 records a Unknown severity vulnerability in liveupdate: Reference count incoming FLB data. 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 Aug 28, 2026Updated Aug 28, 2026Source checked Aug 28, 2026First seen by HOL Aug 28, 2026Material review Aug 28, 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	>=cab056f2aae7250af50e503b81a80dfc567a1acd <725ada0273a0f48a67fd59cc518d7f8055fe3d5c \|\| >=cab056f2aae7250af50e503b81a80dfc567a1acd <d8e47bd066d7e626f9f45d416182d585b7e18b9b	725ada0273a0f48a67fd59cc518d7f8055fe3d5c, d8e47bd066d7e626f9f45d416182d585b7e18b9b
Linux/Linuxgeneric	7.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 725ada0273a0f48a67fd59cc518d7f8055fe3d5c if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 28, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: liveupdate: Reference count incoming FLB data Increment the incoming FLB refcount in liveupdate_flb_get_incoming() so that the FLB structure cannot be freed while the caller is actively using it. Add an additional liveupdate_flb_put_incoming() function so the caller can explicitly indicate when it is done using the FLB data. During a Live Update, a subsystem might need to hold onto the incoming File-Lifecycle-Bound (FLB) data for an extended period, such as during device enumeration. Incrementing the reference count guarantees that the data remains valid and accessible until the subsystem releases it, preventing future use-after-free bugs.

Quoted source text, attributed separately from HOL analysis.