ring-buffer: Prevent subbuf order change when resizing is disabled (CVE-2026-74634) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-74634

ring-buffer: Prevent subbuf order change when resizing is disabled

Answer in brief

CVE-2026-74634 records a Unknown severity vulnerability in ring-buffer: Prevent subbuf order change when resizing is disabled. 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 Aug 22, 2026Updated Aug 22, 2026Source checked Aug 22, 2026First seen by HOL Aug 22, 2026Material review Aug 22, 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	>=f9b94daa542a8d2532f0930f01cd9aec2d19621b <b45b91db41379ee5fb36c187d6d7c37b725cbe8e \|\| >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <62978cf6347972c04130e4e841ba404504d92b32 \|\| >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <7568e9e717e7540bd05bcc007f5d76fcaff3cdff \|\| >=f9b94daa542a8d2532f0930f01cd9aec2d19621b <bf98d7b0d5a99991e47e66cee4eb1d3fa514be97	b45b91db41379ee5fb36c187d6d7c37b725cbe8e, 62978cf6347972c04130e4e841ba404504d92b32, 7568e9e717e7540bd05bcc007f5d76fcaff3cdff, bf98d7b0d5a99991e47e66cee4eb1d3fa514be97
Linux/Linuxgeneric	6.8	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to b45b91db41379ee5fb36c187d6d7c37b725cbe8e if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 22, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Prevent subbuf order change when resizing is disabled Because ring_buffer_subbuf_order_set() frees buffer pages, we can't allow it when resizing is disabled. A non-consuming reader is at risk of use-after-free (rb_advance_iter()). Return -EBUSY on resize_disabled, matching ring_buffer_resize() behaviour.

Quoted source text, attributed separately from HOL analysis.