arm64: RSI: fix field-spanning write warning in attestation token init (CVE-2026-93266) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-93266

arm64: RSI: fix field-spanning write warning in attestation token init

Answer in brief

CVE-2026-93266 records a Unknown severity vulnerability in arm64: RSI: fix field-spanning write warning in attestation token init. 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 24, 2026Updated Sep 24, 2026Source checked Sep 25, 2026First seen by HOL Sep 25, 2026Material review Sep 24, 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	>=b880a80011f56880f32bde47fc6af313359f926b <e505092cb200d430d5b8d8d3e926d45f29474ba3 \|\| >=b880a80011f56880f32bde47fc6af313359f926b <d29a8ee271da17b5e32d7a76a9c78d43f66447ca \|\| >=b880a80011f56880f32bde47fc6af313359f926b <221049874b6a78c7d87bc826581b0695cd338e2b	e505092cb200d430d5b8d8d3e926d45f29474ba3, d29a8ee271da17b5e32d7a76a9c78d43f66447ca, 221049874b6a78c7d87bc826581b0695cd338e2b
Linux/Linuxgeneric	6.13	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to e505092cb200d430d5b8d8d3e926d45f29474ba3 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 24, 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: arm64: RSI: fix field-spanning write warning in attestation token init The challenge is passed in registers a1 through a8. However, copying to &regs.a1 makes FORTIFY treat the destination as the single a1 field, resulting in a field-spanning write warning. [1] Overlay the SMCCC register structure with an RSI-specific argument layout and copy the challenge into an explicit 64-byte array. This keeps the existing a1-a8 argument encoding while giving the copy a correctly sized destination object. [1] memcpy: detected field-spanning write (size 64) of single field "&regs.a1" at ./arch/arm64/include/asm/rsi_cmds.h:119 (size 8) WARNING: ./arch/arm64/include/asm/rsi_cmds.h:119 at rsi_attestation_token_init+0xdc/0xf8 [arm_cca_guest], CPU#0: cat/3314

Quoted source text, attributed separately from HOL analysis.