rtase: fix double free of multi-frag skb on DMA map failure (CVE-2026-74545) | HOL Guard CVE

Critical · CVSS 9.8CVE-2026-74545

rtase: fix double free of multi-frag skb on DMA map failure

Answer in brief

CVE-2026-74545 records a Critical severity (CVSS 9.8) vulnerability in rtase: fix double free of multi-frag skb on DMA map failure. 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 15, 2026Updated Aug 17, 2026Source checked Sep 30, 2026First seen by HOL Aug 15, 2026Material review Aug 17, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.8
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 9.8. 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	>=d6e882b89fdf80be0ab4f914ec10f75215e49495 <4f09172aff5f73a5e914f4fbc0d00a1c2ea9f7cb \|\| >=d6e882b89fdf80be0ab4f914ec10f75215e49495 <db986098f30881fafcc752800aa3b13fd289c922 \|\| >=d6e882b89fdf80be0ab4f914ec10f75215e49495 <de691dc3227b061c4d0beba9f0128fe1ff33dd68 \|\| >=d6e882b89fdf80be0ab4f914ec10f75215e49495 <6fb7b769d6ed6d1d2e02af4a80e57a2477f35086	4f09172aff5f73a5e914f4fbc0d00a1c2ea9f7cb, db986098f30881fafcc752800aa3b13fd289c922, de691dc3227b061c4d0beba9f0128fe1ff33dd68, 6fb7b769d6ed6d1d2e02af4a80e57a2477f35086
Linux/Linuxgeneric	6.12	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 4f09172aff5f73a5e914f4fbc0d00a1c2ea9f7cb if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 15, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: rtase: fix double free of multi-frag skb on DMA map failure In rtase_start_xmit(), when the head buffer DMA mapping fails after rtase_xmit_frags() has mapped all fragments, the error path clears the fragment descriptors with rtase_tx_clear_range(), which frees the skb through the last-frag slot and accounts tx_dropped. Control then falls through to the common error label, which frees the same skb a second time and counts it again. Return right after clearing the fragments when the skb owns frags; the no-frag case still drops through and frees the head skb once.

Quoted source text, attributed separately from HOL analysis.