net/sched: defer qdisc freeing after failed creation (CVE-2026-98017) | HOL Guard CVE

High · CVSS 7.8CVE-2026-98017

net/sched: defer qdisc freeing after failed creation

Answer in brief

CVE-2026-98017 records a High severity (CVSS 7.8) vulnerability in net/sched: defer qdisc freeing after failed creation. 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 25, 2026Updated Sep 25, 2026Source checked Sep 25, 2026First seen by HOL Sep 25, 2026Material review Sep 25, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.8
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.8. 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	>=51ab2994c387c80b45caf8b8067b3f3b97771d25 <20bf6fa34b345333971bd4464a322cce87b83f4e \|\| >=51ab2994c387c80b45caf8b8067b3f3b97771d25 <156a3bab69744e9225bb9eff8c5cc53da18d5a2e \|\| >=51ab2994c387c80b45caf8b8067b3f3b97771d25 <5bfe927c5b4b290fad529186218c728589b4b101 \|\| >=51ab2994c387c80b45caf8b8067b3f3b97771d25 <e6662f2100f8d33b0f4d0047c219efd6bba186ea	20bf6fa34b345333971bd4464a322cce87b83f4e, 156a3bab69744e9225bb9eff8c5cc53da18d5a2e, 5bfe927c5b4b290fad529186218c728589b4b101, e6662f2100f8d33b0f4d0047c219efd6bba186ea
Linux/Linuxgeneric	4.16	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 20bf6fa34b345333971bd4464a322cce87b83f4e if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 25, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: net/sched: defer qdisc freeing after failed creation An RTM_NEWQDISC request can make clsact bind a populated shared ingress block during ->init(), publishing an embedded mini_Qdisc to lockless readers. If the same request has an invalid TCA_RATE, estimator setup fails after ->init(); the unwind removes the pointer but synchronously frees its containing qdisc while tc_run() may still hold it. Retire failed qdiscs through the same RCU helper as normal destruction. Inline the synchronous free into the callback now that no direct callers remain.

Quoted source text, attributed separately from HOL analysis.