9.8
CRITICAL CVSS 3.1
CVE-2026-64046
net: tls: prevent chain-after-chain in plain text SG
Description

In the Linux kernel, the following vulnerability has been resolved: net: tls: prevent chain-after-chain in plain text SG Sashiko points out that if end = 0 (start != 0) the current code will create a chain link to content type right after the wrap link: This would create a chain where the wrap link points directly to another chain link. The scatterlist API sg_next iterator does not recursively resolve consecutive chain links. meaning this is illegal input to crypto. The wrapping link is unnecessary if end = 0. end is the entry after the last one used so end = 0 means there's nothing pushed after the wrap: end start i v v v [ ]...[ ][ d ][ d ][ d ][ d ][rsv for wrap] Skip the wrapping in this case. TLS 1.3 can use the "wrapping slot" for it's chaining if end = 0. This avoids the chain-after-chain. Move the wrap chaining before marking END and chaining off content type, that feels like more logical ordering to me, but should not matter from functional perspective.

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-2026-64046 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
Update the Linux kernel to resolve chain-after-chain issue in TLS plain text handling.
  • Update the Linux kernel to the latest version.
  • Apply relevant security patches for the net:tls component.
  • Verify TLS configuration for correct chaining.
  • Restart affected network services if necessary.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-64046 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-2026-64046 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-2026-64046 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-64046 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': '49a5faaa471ddcd37b6893970c9916eb836e7c31', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '91359966e247c0244c66d50bbb8e74aefa4321c3', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '410351158dfef2d67fea6603680b3a6013c6ed9d', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': 'acdc12b71c9aa4be5dcd2c8062753c6d2033e235', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': '929b1548e63ac72e104c07d8ee8cbbeeba2fa89a', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': 'af855f4c966afafef74faf8390c7b86568c0d46d', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': 'b9c015ef1a7bf1e8dc67f21c6381f36deb2c3a36', 'versionType': 'git'}, {'status': 'affected', 'version': '9aaaa56845a06aeabdd597cbe19492dc01f281ec', 'lessThan': 'ff26a0e8377dec07e4a7230db7675bed1b9a6d03', '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: prevent chain-after-chain in plain text SG Sashiko points out that if end = 0 (start != 0) the current code will create a chain link to content type right after the wrap link: This would create a chain where the wrap link points directly to another chain link. The scatterlist API sg_next iterator does not recursively resolve consecutive chain links. meaning this is illegal input to crypto. The wrapping link is unnecessary if end = 0. end is the entry after the last one used so end = 0 means there's nothing pushed after the wrap: end start i v v v [ ]...[ ][ d ][ d ][ d ][ d ][rsv for wrap] Skip the wrapping in this case. TLS 1.3 can use the "wrapping slot" for it's chaining if end = 0. This avoids the chain-after-chain. Move the wrap chaining before marking END and chaining off content type, that feels like more logical ordering to me, but should not matter from functional perspective.
    Added Reference https://git.kernel.org/stable/c/410351158dfef2d67fea6603680b3a6013c6ed9d
    Added Reference https://git.kernel.org/stable/c/49a5faaa471ddcd37b6893970c9916eb836e7c31
    Added Reference https://git.kernel.org/stable/c/91359966e247c0244c66d50bbb8e74aefa4321c3
    Added Reference https://git.kernel.org/stable/c/929b1548e63ac72e104c07d8ee8cbbeeba2fa89a
    Added Reference https://git.kernel.org/stable/c/acdc12b71c9aa4be5dcd2c8062753c6d2033e235
    Added Reference https://git.kernel.org/stable/c/af855f4c966afafef74faf8390c7b86568c0d46d
    Added Reference https://git.kernel.org/stable/c/b9c015ef1a7bf1e8dc67f21c6381f36deb2c3a36
    Added Reference https://git.kernel.org/stable/c/ff26a0e8377dec07e4a7230db7675bed1b9a6d03
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.