bpf: Copy per-CPU map value padding in copy_map_value_long() (CVE-2026-93174) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-93174

bpf: Copy per-CPU map value padding in copy_map_value_long()

Answer in brief

CVE-2026-93174 records a Unknown severity vulnerability in bpf: Copy per-CPU map value padding in copy_map_value_long(). 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	>=448325199f574d33824dbf9121efb03558412966 <953e85da53541a8dc3e7ad4e8532f29a34a32eae \|\| >=448325199f574d33824dbf9121efb03558412966 <003bf840ed3326bd01396ce7d5b431cef0d371e7 \|\| >=448325199f574d33824dbf9121efb03558412966 <5e9f69829835521aa2942d1d14bd0990fbc6991e \|\| >=448325199f574d33824dbf9121efb03558412966 <ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef \|\| >=448325199f574d33824dbf9121efb03558412966 <7cf9cd98cf6f0df3befc167ca6b54c07014d71de	953e85da53541a8dc3e7ad4e8532f29a34a32eae, 003bf840ed3326bd01396ce7d5b431cef0d371e7, 5e9f69829835521aa2942d1d14bd0990fbc6991e, ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef, 7cf9cd98cf6f0df3befc167ca6b54c07014d71de
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 953e85da53541a8dc3e7ad4e8532f29a34a32eae 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: Copy per-CPU map value padding in copy_map_value_long() In kernel, per-CPU map elements are stored with round_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the rounded size for each CPU into a temporary buffer. However, copy_map_value_long() passes 'map->value_size' to bpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies around those fields with memcpy(), and does not copy the tail padding between 'map->value_size' and round_up(map->value_size, 8). The temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a result, when the per-CPU map's value size is not equal to round_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return stale heap contents from that padding to user space. The same issue applies to bpf_iter for per-CPU maps. Pass round_up(map->value_size, 8) to bpf_obj_memcpy() from copy_map_value_long(), so per-CPU maps both with and without special fields copy the entire per-CPU slot. Remove the now redundant round_up() from bpf_obj_memcpy()'s long_memcpy path.

Quoted source text, attributed separately from HOL analysis.