bpf, x86: Fix trampoline stack size for 128-bit arguments (CVE-2026-90358) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-90358

bpf, x86: Fix trampoline stack size for 128-bit arguments

Answer in brief

CVE-2026-90358 records a Unknown severity vulnerability in bpf, x86: Fix trampoline stack size for 128-bit arguments. 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	>=a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 <4aed2346fa9b88d458eeb8c01123f3c07585a675 \|\| >=a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 <40f3bfbbb222b92278f3797614b70f68d46824ac \|\| >=a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 <a6d7d7a253c550e74b0651897fe313c2f9b2301f \|\| >=a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2 <814cba835ef648e0c5eb79505c96c0493b29eea6	4aed2346fa9b88d458eeb8c01123f3c07585a675, 40f3bfbbb222b92278f3797614b70f68d46824ac, a6d7d7a253c550e74b0651897fe313c2f9b2301f, 814cba835ef648e0c5eb79505c96c0493b29eea6
Linux/Linuxgeneric	6.1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 4aed2346fa9b88d458eeb8c01123f3c07585a675 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: bpf, x86: Fix trampoline stack size for 128-bit arguments btf_distill_func_proto() accepts a function argument up to 16 bytes, so a 128-bit scalar such as __int128 reaches the x86 trampoline with arg_size == 16. But the current implementation assumes an __int128 argument only needs one register, so the register save area is under-allocated and save_args() overwrites adjacent stack slots. Compute the register count from arg_size for all arguments to fix it.

Quoted source text, attributed separately from HOL analysis.