net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size (CVE-2026-98027) | HOL Guard CVE

High · CVSS 7.0CVE-2026-98027

net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size

Answer in brief

CVE-2026-98027 records a High severity (CVSS 7.0) vulnerability in net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size. 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: High · CVSS 7.0
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.0. 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	>=da7dc87553046a43be1620a783ce3d9f6583d322 <44cd4674d9aa5bdf793b8a8b481c9e8536ed6070 \|\| >=da7dc87553046a43be1620a783ce3d9f6583d322 <7a683c2b062810bca203e41866389daf387c235b \|\| >=da7dc87553046a43be1620a783ce3d9f6583d322 <cda5ac8fe8ac8e80b1703ebb8c4250726fc19739 \|\| >=da7dc87553046a43be1620a783ce3d9f6583d322 <b1fffc273112e7284c5b705e186b43b5770cd3d5	44cd4674d9aa5bdf793b8a8b481c9e8536ed6070, 7a683c2b062810bca203e41866389daf387c235b, cda5ac8fe8ac8e80b1703ebb8c4250726fc19739, b1fffc273112e7284c5b705e186b43b5770cd3d5
Linux/Linuxgeneric	5.4	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 44cd4674d9aa5bdf793b8a8b481c9e8536ed6070 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: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size mv88e6xxx_get_rxnfc() uses rxnfc->rule_cnt as the write index while dumping the policy IDR, clobbering the input value before it has been looked at. That input is the number of entries the caller had room for. ETHTOOL_GRXCLSRLALL requires no CAP_NET_ADMIN and the ioctl sizes the buffer from the rule_cnt userspace passes in, so once an admin has installed policy rules any user can ask for fewer slots than there are rules and run off the end of the allocation. A rule_cnt of 0 leaves the buffer pointer NULL and the walk dereferences it. Count into a local so the caller's limit survives the walk, and stop with -EMSGSIZE once it is reached.

Quoted source text, attributed separately from HOL analysis.