drop_monitor: fix size calculations for 64-bit attributes (CVE-2026-68287) | HOL Guard CVE

High · CVSS 7.5CVE-2026-68287

drop_monitor: fix size calculations for 64-bit attributes

Answer in brief

CVE-2026-68287 records a High severity (CVSS 7.5) vulnerability in drop_monitor: fix size calculations for 64-bit attributes. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), 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 Aug 10, 2026Updated Sep 21, 2026Source checked Sep 24, 2026First seen by HOL Aug 10, 2026Material review Sep 21, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. 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), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=ca30707dee2bc8bc81cfd8b4277fe90f7ca6df1f <4a9e30764e80693bcf875c776170edce20f94fe0 \|\| >=ca30707dee2bc8bc81cfd8b4277fe90f7ca6df1f <7089f7ab99c89f443c92d8fcc585e63f2727f0b3	4a9e30764e80693bcf875c776170edce20f94fe0, 7089f7ab99c89f443c92d8fcc585e63f2727f0b3
Linux/Linuxgeneric	5.4	Not reported
Linux/Linuxgeneric	>=ca30707dee2bc8bc81cfd8b4277fe90f7ca6df1f <6048ed2dfb33426c8aef32f8d225ea91c66813db \|\| >=ca30707dee2bc8bc81cfd8b4277fe90f7ca6df1f <925669d4cfd47a9019ab29b40676215bab5dae35 \|\| >=ca30707dee2bc8bc81cfd8b4277fe90f7ca6df1f <4a9e30764e80693bcf875c776170edce20f94fe0 \|\| >=ca30707dee2bc8bc81cfd8b4277fe90f7ca6df1f <7089f7ab99c89f443c92d8fcc585e63f2727f0b3	6048ed2dfb33426c8aef32f8d225ea91c66813db, 925669d4cfd47a9019ab29b40676215bab5dae35, 4a9e30764e80693bcf875c776170edce20f94fe0, 7089f7ab99c89f443c92d8fcc585e63f2727f0b3

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 4a9e30764e80693bcf875c776170edce20f94fe0; Linux/Linux to 6048ed2dfb33426c8aef32f8d225ea91c66813db if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 21, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 10, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: drop_monitor: fix size calculations for 64-bit attributes net_dm_packet_report_fill() and net_dm_hw_packet_report_fill() use nla_put_u64_64bit() to append 64-bit attributes (NET_DM_ATTR_PC and NET_DM_ATTR_TIMESTAMP). On 32-bit architectures without CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, nla_put_u64_64bit() may append a 4-byte NET_DM_ATTR_PAD attribute for 64-bit alignment. However, net_dm_packet_report_size() and net_dm_hw_packet_report_size() used nla_total_size(sizeof(u64)) instead of nla_total_size_64bit(sizeof(u64)), budgeting 12 bytes instead of up to 16 bytes. This under-estimation of SKB size can lead to an skb_over_panic() when __nla_reserve() or skb_put() is subsequently called. Fix this by using nla_total_size_64bit(sizeof(u64)) in both size calculations.

Quoted source text, attributed separately from HOL analysis.