net/sched: ets: clamp quantum in parse and fallback paths (CVE-2026-98009) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-98009

net/sched: ets: clamp quantum in parse and fallback paths

Answer in brief

CVE-2026-98009 records a Unknown severity vulnerability in net/sched: ets: clamp quantum in parse and fallback paths. 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: 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	>=dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 <99ae477b892e203a37985ebc56f0063e072f7f4b \|\| >=dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 <8f80b113dea0bed3c1a31a4224b72775cd9ec52d \|\| >=dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 <de22c30ec5598aca8797f02082d2ee1358dfa3ff \|\| >=dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 <1c38487f46b243bfeefec0c0c86023a3904f2214	99ae477b892e203a37985ebc56f0063e072f7f4b, 8f80b113dea0bed3c1a31a4224b72775cd9ec52d, de22c30ec5598aca8797f02082d2ee1358dfa3ff, 1c38487f46b243bfeefec0c0c86023a3904f2214
Linux/Linuxgeneric	5.6	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 99ae477b892e203a37985ebc56f0063e072f7f4b 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: ets: clamp quantum in parse and fallback paths ets_qdisc_change() falls back to psched_mtu() with no floor for bands without an explicit quantum. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so a zero psched_mtu on a headerless device makes the deficit-refill loop spin under the qdisc lock. Move the floor into ets_quantum_parse() so explicitly configured quanta are also clamped to [256, 1<<20], not just the fallback path. Conditions to recreate the bug: CONFIG_NET_SCH_ETS=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root ets bands 3 strict 2 quanta 1 1

Quoted source text, attributed separately from HOL analysis.