CVE-2026-64047

In the Linux kernel, the following vulnerability has been resolved: net: tls: fix off-by-one in sg_chain entry count for wrapped sk_msg ring When an sk_msg scatterlist ring wraps (sg.end sg.data[msg_pl->sg.start], MAX_SKB_FRAGS - msg_pl->sg.start + 1, msg_pl->sg.data); This places the chain pointer at sg_chain(data[start], (MAX_SKB_FRAGS - msg_start + 1) .. = &data[start] + (MAX_SKB_FRAGS - msg_start + 1) - 1 = data[start + (MAX_SKB_FRAGS - start + 1) - 1] = data[MAX_SKB_FRAGS] instead of the true last entry. This is likely due to a "race" of the commit under Fixes landing close to commit 031097d9e079 ("bpf: sk_msg, zap ingress queue on psock down") Convert to ARRAY_SIZE and drop the data[start] / - start (as suggested by Sabrina).

What this means for your business

It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
FIRST's prediction model gives it a 0.5% chance of attack attempts being seen in the next 30 days, ranking above 42% of all known flaws.

What to do

1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

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Scoring

CVSS: 9.8 (v3.1)
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-193
Assigned by: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Dates

Published: 2026-07-19
Last modified: 2026-09-02
Sources: NVD

Affected products

Linux Linux Kernel5.4.14 - 5.5, 5.5.1 - 5.10.258, 5.11 - 5.15.209, 5.16 - 6.1.175, 6.2 - 6.6.142, 6.7 - 6.12.92, 6.13 - 6.18.34, 6.19 - 7.0.11, 5.5, 7.1

As listed in the NVD configuration data. Not a statement about your estate.