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7.8
HIGH CVSS 3.1
CVE-2026-68297
tipc: fix u16 MTU truncation in media and bearer MTU validation
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: tipc: fix u16 MTU truncation in media and bearer MTU validation Both TIPC_NL_MEDIA_SET and TIPC_NL_BEARER_SET accept user-supplied MTU values but only enforce a minimum bound, not a maximum. When a user sets the MTU to a value exceeding U16_MAX (65535), it passes validation but is silently truncated when assigned to u16 fields l->mtu and l->advertised_mtu in tipc_link_create(). Values like 65536 (0x10000) truncate to 0, causing a division by zero in tipc_link_set_queue_limits() which computes TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE). Other overflowing values (e.g. 65537-131071) produce small incorrect MTU values, resulting in link malfunction behaviors. Crash stack (triggered as unprivileged user via user namespace): tipc_link_set_queue_limits net/tipc/link.c:2531 tipc_link_create net/tipc/link.c:520 tipc_node_check_dest net/tipc/node.c:1279 tipc_disc_rcv net/tipc/discover.c:252 tipc_rcv net/tipc/node.c:2129 tipc_udp_recv net/tipc/udp_media.c:392 Two independent paths lack the upper bound check: 1. tipc_udp_mtu_bad() -- called from __tipc_nl_media_set() (MEDIA_SET) 2. inline check in __tipc_nl_bearer_set() at bearer.c:1160 (BEARER_SET) Fix both by rejecting MTU values above U16_MAX.

Details
INFO

Published Date :

Aug. 10, 2026, 1:20 p.m.

Last Modified :

Aug. 17, 2026, 5:18 a.m.

Remotely Exploit :

No

Source :

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

The following products are affected by CVE-2026-68297 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.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Scoring
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 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Update the Linux kernel to validate MTU values and prevent truncation issues.
  • Update the Linux kernel to the latest version.
  • Ensure MTU values do not exceed U16_MAX.
  • Validate user-supplied MTU values for upper bounds.
  • Apply the fix rejecting MTU values above U16_MAX.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-68297.

URL Resource
https://git.kernel.org/stable/c/1b8fb5a20508bfb0db854e01214888c761b3a911
https://git.kernel.org/stable/c/9f29cd8a8e7901a2617c8064ce9f50fc67b97cb8
https://git.kernel.org/stable/c/c1cda72f6acec02ebd45d913bf8527ff77336ba6
https://git.kernel.org/stable/c/f02334a9e378f7e07232b26dc3d2ab353339f040
https://git.kernel.org/stable/c/f4013598b69457dbea350df52e52daea6faef8eb
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-68297 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-2026-68297 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-2026-68297 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-68297 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

    Aug. 17, 2026

    Action Type Old Value New Value
    Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'f02334a9e378f7e07232b26dc3d2ab353339f040', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'f4013598b69457dbea350df52e52daea6faef8eb', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': '1b8fb5a20508bfb0db854e01214888c761b3a911', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'c1cda72f6acec02ebd45d913bf8527ff77336ba6', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': '9f29cd8a8e7901a2617c8064ce9f50fc67b97cb8', 'versionType': 'git'}], 'programFiles': ['net/tipc/netlink.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.18'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.18', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc5', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/netlink.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'f02334a9e378f7e07232b26dc3d2ab353339f040', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'f4013598b69457dbea350df52e52daea6faef8eb', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': '1b8fb5a20508bfb0db854e01214888c761b3a911', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'c1cda72f6acec02ebd45d913bf8527ff77336ba6', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': '9f29cd8a8e7901a2617c8064ce9f50fc67b97cb8', 'versionType': 'git'}], 'programFiles': ['net/tipc/netlink.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.18'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.18', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/netlink.c'], 'defaultStatus': 'affected'}]
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Aug. 13, 2026

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

    Aug. 10, 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': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'f02334a9e378f7e07232b26dc3d2ab353339f040', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'f4013598b69457dbea350df52e52daea6faef8eb', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': '1b8fb5a20508bfb0db854e01214888c761b3a911', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': 'c1cda72f6acec02ebd45d913bf8527ff77336ba6', 'versionType': 'git'}, {'status': 'affected', 'version': '901271e0403af638c224987c2a4e55cebade7e91', 'lessThan': '9f29cd8a8e7901a2617c8064ce9f50fc67b97cb8', 'versionType': 'git'}], 'programFiles': ['net/tipc/netlink.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.18'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.18', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc5', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/netlink.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: tipc: fix u16 MTU truncation in media and bearer MTU validation Both TIPC_NL_MEDIA_SET and TIPC_NL_BEARER_SET accept user-supplied MTU values but only enforce a minimum bound, not a maximum. When a user sets the MTU to a value exceeding U16_MAX (65535), it passes validation but is silently truncated when assigned to u16 fields l->mtu and l->advertised_mtu in tipc_link_create(). Values like 65536 (0x10000) truncate to 0, causing a division by zero in tipc_link_set_queue_limits() which computes TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE). Other overflowing values (e.g. 65537-131071) produce small incorrect MTU values, resulting in link malfunction behaviors. Crash stack (triggered as unprivileged user via user namespace): tipc_link_set_queue_limits net/tipc/link.c:2531 tipc_link_create net/tipc/link.c:520 tipc_node_check_dest net/tipc/node.c:1279 tipc_disc_rcv net/tipc/discover.c:252 tipc_rcv net/tipc/node.c:2129 tipc_udp_recv net/tipc/udp_media.c:392 Two independent paths lack the upper bound check: 1. tipc_udp_mtu_bad() -- called from __tipc_nl_media_set() (MEDIA_SET) 2. inline check in __tipc_nl_bearer_set() at bearer.c:1160 (BEARER_SET) Fix both by rejecting MTU values above U16_MAX.
    Added Reference https://git.kernel.org/stable/c/1b8fb5a20508bfb0db854e01214888c761b3a911
    Added Reference https://git.kernel.org/stable/c/9f29cd8a8e7901a2617c8064ce9f50fc67b97cb8
    Added Reference https://git.kernel.org/stable/c/c1cda72f6acec02ebd45d913bf8527ff77336ba6
    Added Reference https://git.kernel.org/stable/c/f02334a9e378f7e07232b26dc3d2ab353339f040
    Added Reference https://git.kernel.org/stable/c/f4013598b69457dbea350df52e52daea6faef8eb
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.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
Privileges Required
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Scope
Confidentiality Impact
Integrity Impact
Availability Impact