nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo (CVE-2026-89673) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89673

nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo

Answer in brief

CVE-2026-89673 records a Unknown severity vulnerability in nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo. 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 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 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	>=efcae97fa425ca6db9d126e37daccf2d7225cb09 <74015b7be806ad9e21d46f7bd2831df280c6c783 \|\| >=efcae97fa425ca6db9d126e37daccf2d7225cb09 <41ebca28e17f84293650598f86bd69532ec1a8e0 \|\| >=efcae97fa425ca6db9d126e37daccf2d7225cb09 <62e5949f0dd5ec837af144860ff908369df4c7c9 \|\| >=efcae97fa425ca6db9d126e37daccf2d7225cb09 <8b989aaec85e1293a871d602590c951fe44b8647	74015b7be806ad9e21d46f7bd2831df280c6c783, 41ebca28e17f84293650598f86bd69532ec1a8e0, 62e5949f0dd5ec837af144860ff908369df4c7c9, 8b989aaec85e1293a871d602590c951fe44b8647
Linux/Linuxgeneric	>=6.4.16 <6.12.109 \|\| >=6.4.16 <6.18.50 \|\| >=6.4.16 <7.2.4 \|\| >=6.4.16 <7.3-rc1	6.12.109, 6.18.50, 7.2.4, 7.3-rc1

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 74015b7be806ad9e21d46f7bd2831df280c6c783; Linux/Linux to 6.12.109 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo nfsd4_ff_encode_getdeviceinfo() computes the da_addr_body reservation as 16 + netid_len + addr_len, but the subsequent xdr_encode_opaque() calls emit 8 + round_up(netid_len, 4) + round_up(addr_len, 4) bytes. The mismatch means the declared da_addr_body length exceeds the actual encoded data by 2-8 bytes on every flexfile GETDEVICEINFO reply, leaking stale reply-page content to the client and mis-aligning the subsequent version list decode. Use xdr_align_size() for each string length to match what xdr_encode_opaque() actually writes.

Quoted source text, attributed separately from HOL analysis.