9.8
CRITICAL CVSS 3.1
CVE-2026-64047
net: tls: fix off-by-one in sg_chain entry count for wrapped sk_msg ring
Description

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.start), tls_push_record() chains the tail portion of the ring to the head using sg_chain(). An extra entry in the sg array is reserved for this: struct sk_msg_sg { [...] /* The extra two elements: * 1) used for chaining the front and sections when the list becomes * partitioned (e.g. end < start). The crypto APIs require the * chaining; * 2) to chain tailer SG entries after the message. */ struct scatterlist data[MAX_MSG_FRAGS + 2]; The current code uses MAX_SKB_FRAGS + 1 as the ring size: sg_chain(&msg_pl->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).

INFO

Published Date :

July 19, 2026, 4:17 p.m.

Last Modified :

July 20, 2026, 3:17 p.m.

Remotely Exploit :

Yes !

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-64047 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Apply the Linux kernel patch to fix the off-by-one error in sk_msg ring handling.
  • Update the Linux kernel to the patched version.
  • Recompile the kernel if necessary.
  • Restart the system to apply changes.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-64047 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-64047 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-64047 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-64047 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 20, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 19, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '73963a375885d5ccb7def39fd0b4f542e0f343dd', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '47110c3a9ac247b688657337f5981efcfcb240dc', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '84158c2997159df4a0d70cd9c46774512d32a522', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '131ef12057d92b77b636321b7849c69222405a97', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '66339b71f105e6f83e0da3b9583d95077534fe1d', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': 'eca989eab4b2599dcb02f72140a7c08f08838520', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '2fb0dc7e0099686c4e9d2732745d8a31b18c3628', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '285943c6e7ca309bbea84b253745154241d9788a', 'versionType': 'git'}, {'status': 'affected', 'version': 'd529d6c9f7e3aaeac13c4948f79799ccb825f29d', 'versionType': 'git'}, {'status': 'affected', 'version': '5.4.14', 'lessThan': '5.5', 'versionType': 'semver'}], 'programFiles': ['net/tls/tls_sw.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.5'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.5', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.258', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.209', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.175', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.142', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tls/tls_sw.c'], 'defaultStatus': 'affected'}]
    Added Description 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.start), tls_push_record() chains the tail portion of the ring to the head using sg_chain(). An extra entry in the sg array is reserved for this: struct sk_msg_sg { [...] /* The extra two elements: * 1) used for chaining the front and sections when the list becomes * partitioned (e.g. end < start). The crypto APIs require the * chaining; * 2) to chain tailer SG entries after the message. */ struct scatterlist data[MAX_MSG_FRAGS + 2]; The current code uses MAX_SKB_FRAGS + 1 as the ring size: sg_chain(&msg_pl->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).
    Added Reference https://git.kernel.org/stable/c/131ef12057d92b77b636321b7849c69222405a97
    Added Reference https://git.kernel.org/stable/c/285943c6e7ca309bbea84b253745154241d9788a
    Added Reference https://git.kernel.org/stable/c/2fb0dc7e0099686c4e9d2732745d8a31b18c3628
    Added Reference https://git.kernel.org/stable/c/47110c3a9ac247b688657337f5981efcfcb240dc
    Added Reference https://git.kernel.org/stable/c/66339b71f105e6f83e0da3b9583d95077534fe1d
    Added Reference https://git.kernel.org/stable/c/73963a375885d5ccb7def39fd0b4f542e0f343dd
    Added Reference https://git.kernel.org/stable/c/84158c2997159df4a0d70cd9c46774512d32a522
    Added Reference https://git.kernel.org/stable/c/eca989eab4b2599dcb02f72140a7c08f08838520
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.