netfilter: nf_conntrack: use get_unaligned_be32() in tcp_sack() (CVE-2026-97417) | HOL Guard CVE

High · CVSS 7.5CVE-2026-97417

netfilter: nf_conntrack: use get_unaligned_be32() in tcp_sack()

Answer in brief

CVE-2026-97417 records a High severity (CVSS 7.5) vulnerability in netfilter: nf_conntrack: use get_unaligned_be32() in tcp_sack(). The current sources do not mark it as known exploited. The current feed maps 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 24, 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 7.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
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). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7ecfa46a536578a7ed335ddf31a854127268c27c \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <4abc1af7ac209c066f4e5dd75cdd56876e5829a9 \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d3bf9eae486490832bd08fd62ab0ac601f346bd4 \|\| >=0 <6.12.111 \|\| >=0 <6.18.53	7ecfa46a536578a7ed335ddf31a854127268c27c, 4abc1af7ac209c066f4e5dd75cdd56876e5829a9, d3bf9eae486490832bd08fd62ab0ac601f346bd4, 6.12.111, 6.18.53

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux.
Review the reported fix. Update Linux/Linux to 7ecfa46a536578a7ed335ddf31a854127268c27c if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 24, 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: netfilter: nf_conntrack: use get_unaligned_be32() in tcp_sack() The timestamp-only fast path dereferences the option stream as *(__be32 *)ptr, which assumes 4-byte alignment that the TCP option stream does not guarantee. Use get_unaligned_be32() instead, which reads the value safely and already returns host byte order, so the htonl() on the comparison constant can be dropped. This matches the existing get_unaligned_be32() use later in the same function.

Quoted source text, attributed separately from HOL analysis.