cxl/features: Reject Set Features output buffer smaller than the header (CVE-2026-93078) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-93078

cxl/features: Reject Set Features output buffer smaller than the header

Answer in brief

CVE-2026-93078 records a Unknown severity vulnerability in cxl/features: Reject Set Features output buffer smaller than the header. 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 17, 2026Updated Sep 17, 2026Source checked Sep 17, 2026First seen by HOL Sep 17, 2026Material review Sep 17, 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	>=eb5dfcb9e36d0e46089fec777d911313c1876fa3 <1281dc84c81577b51e2b61c24617c9f44b2cdb99 \|\| >=eb5dfcb9e36d0e46089fec777d911313c1876fa3 <16b7c99eff030c6ea11ca24efa4b9f989cc74093 \|\| >=eb5dfcb9e36d0e46089fec777d911313c1876fa3 <cde18d6c1d913a67ab0afd3d9475ece4be79da50	1281dc84c81577b51e2b61c24617c9f44b2cdb99, 16b7c99eff030c6ea11ca24efa4b9f989cc74093, cde18d6c1d913a67ab0afd3d9475ece4be79da50
Linux/Linuxgeneric	6.15	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 1281dc84c81577b51e2b61c24617c9f44b2cdb99 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 17, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: cxl/features: Reject Set Features output buffer smaller than the header cxlctl_set_feature() sizes its output buffer from the user's fwctl_rpc.out_len but never checks it is large enough to hold even the fwctl_rpc_cxl_out header. With out_len == 0 , kvzalloc() returns ZERO_SIZE_PTR, which passes the !rpc_out check, the subsequent rpc_out->size = 0 then writes through the poison pointer. Reject requests whose output buffer can't hold the response header, before allocating. The Set Feature reply carries no payload, so the header is all that is required.

Quoted source text, attributed separately from HOL analysis.