CVE-2026-68455
liveupdate: validate session type before performing operation
Description
In the Linux kernel, the following vulnerability has been resolved: liveupdate: validate session type before performing operation The sessions ioctls are not applicable to all session types. PRESERVE_FD is only applicable to outgoing sessions. RETRIEVE_FD and FINISH are only valid for incoming session. Calling a incoming ioctl on an outgoing session is invalid and can cause file handlers to run into unexpected errors. For example, a user can create a (outgoing) session, preserve a memfd, and then immediately do a retrieve without doing a kexec in between. This would result in memfd's retrieve handler to run. The handlers expects to be called from a post-kexec context, and will try to do a kho_restore_vmalloc() or kho_restore_folio() to try and restore memory. KHO catches this (thanks to KHO_PAGE_MAGIC) and returns an error, but since this is considered an internal error and KHO throws out a bunch of WARN()s. Associate a type with each ioctl op and validate the type in luo_session_ioctl() before dispatching the ioctl handler to make sure the op is being called for the right session type.
INFO
Published Date :
Aug. 15, 2026, 6:17 a.m.
Last Modified :
Aug. 17, 2026, 6:17 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Associate session types with ioctl operations.
- Validate session types in luo_session_ioctl before handler dispatch.
- Update the Linux kernel to the latest stable version.
- Apply the 'liveupdate: validate session type' patch.
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-2026-68455.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/3dc8a46d08a8a060d4128e9f497060b8d03c1595 | |
| https://git.kernel.org/stable/c/507e3b479f9c6d85135eb5e1a77fb3fddb259ad8 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-68455 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-2026-68455
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-2026-68455 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-68455 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': '16cec0d265219f14a7fcebcc43aeb69205adba56', 'lessThan': '3dc8a46d08a8a060d4128e9f497060b8d03c1595', 'versionType': 'git'}, {'status': 'affected', 'version': '16cec0d265219f14a7fcebcc43aeb69205adba56', 'lessThan': '507e3b479f9c6d85135eb5e1a77fb3fddb259ad8', 'versionType': 'git'}], 'programFiles': ['kernel/liveupdate/luo_session.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/liveupdate/luo_session.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '16cec0d265219f14a7fcebcc43aeb69205adba56', 'lessThan': '3dc8a46d08a8a060d4128e9f497060b8d03c1595', 'versionType': 'git'}, {'status': 'affected', 'version': '16cec0d265219f14a7fcebcc43aeb69205adba56', 'lessThan': '507e3b479f9c6d85135eb5e1a77fb3fddb259ad8', 'versionType': 'git'}], 'programFiles': ['kernel/liveupdate/luo_session.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/liveupdate/luo_session.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 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': '16cec0d265219f14a7fcebcc43aeb69205adba56', 'lessThan': '3dc8a46d08a8a060d4128e9f497060b8d03c1595', 'versionType': 'git'}, {'status': 'affected', 'version': '16cec0d265219f14a7fcebcc43aeb69205adba56', 'lessThan': '507e3b479f9c6d85135eb5e1a77fb3fddb259ad8', 'versionType': 'git'}], 'programFiles': ['kernel/liveupdate/luo_session.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/liveupdate/luo_session.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: liveupdate: validate session type before performing operation The sessions ioctls are not applicable to all session types. PRESERVE_FD is only applicable to outgoing sessions. RETRIEVE_FD and FINISH are only valid for incoming session. Calling a incoming ioctl on an outgoing session is invalid and can cause file handlers to run into unexpected errors. For example, a user can create a (outgoing) session, preserve a memfd, and then immediately do a retrieve without doing a kexec in between. This would result in memfd's retrieve handler to run. The handlers expects to be called from a post-kexec context, and will try to do a kho_restore_vmalloc() or kho_restore_folio() to try and restore memory. KHO catches this (thanks to KHO_PAGE_MAGIC) and returns an error, but since this is considered an internal error and KHO throws out a bunch of WARN()s. Associate a type with each ioctl op and validate the type in luo_session_ioctl() before dispatching the ioctl handler to make sure the op is being called for the right session type. Added Reference https://git.kernel.org/stable/c/3dc8a46d08a8a060d4128e9f497060b8d03c1595 Added Reference https://git.kernel.org/stable/c/507e3b479f9c6d85135eb5e1a77fb3fddb259ad8