CVE-2026-74631
net: smc: fix splice entry lifetime imbalance in smc_rx_splice
Description
In the Linux kernel, the following vulnerability has been resolved: net: smc: fix splice entry lifetime imbalance in smc_rx_splice smc_rx_splice() passes pages to splice_to_pipe() before taking the references that cover the lifetime of each splice entry. In the VM-backed RMB path, splice_to_pipe() may drop unqueued entries through smc_rx_spd_release(), while queued entries are released later via the pipe buffer callback. The old post-splice accounting also derives the number of queued VM pages from an offset mutated while building the descriptor, and a multi-page splice pairs one sock_hold() with multiple sock_put() calls. Take the page and socket references for every candidate entry before splice_to_pipe(), and drop the matching private state, page reference, and socket reference from smc_rx_spd_release() for entries that never get queued. This fixes a refcount imbalance that can underflow page refcounts and trigger a use-after-free.
INFO
Published Date :
Aug. 22, 2026, 4:16 p.m.
Last Modified :
Aug. 22, 2026, 4:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-74631
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
Solution
- Apply the net: smc: fix splice entry lifetime imbalance patch.
- Update the Linux kernel to the patched version.
- Ensure all kernel modules are properly referenced.
- Review socket reference counting logic.
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-2026-74631.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74631 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-2026-74631
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-2026-74631 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74631 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 22, 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': '9014db202cb764b8e14c53e7bacc81f9a1a2ba7f', 'lessThan': 'c841789e456ec6751342fa800639ce8e82ff0e6b', 'versionType': 'git'}, {'status': 'affected', 'version': '9014db202cb764b8e14c53e7bacc81f9a1a2ba7f', 'lessThan': 'af02c67ce654356c58db20a0bb2db33ace3b07a8', 'versionType': 'git'}, {'status': 'affected', 'version': '9014db202cb764b8e14c53e7bacc81f9a1a2ba7f', 'lessThan': 'ca8342b5fc24c249fdb998468f6a168b457c67e5', 'versionType': 'git'}, {'status': 'affected', 'version': '9014db202cb764b8e14c53e7bacc81f9a1a2ba7f', 'lessThan': '0b7d54cedea5cb158e21925ae0c6c2f5c87ed2a0', 'versionType': 'git'}, {'status': 'affected', 'version': '9014db202cb764b8e14c53e7bacc81f9a1a2ba7f', 'lessThan': '4515c78f4d9fd577270f012efeb062ea58b3682d', 'versionType': 'git'}, {'status': 'affected', 'version': '9014db202cb764b8e14c53e7bacc81f9a1a2ba7f', 'lessThan': '5d9686af2976741bbd79b150d1c9e60b81e7f12e', 'versionType': 'git'}], 'programFiles': ['net/smc/smc_rx.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': '6.1.183', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.152', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.104', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.45', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.9', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/smc/smc_rx.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net: smc: fix splice entry lifetime imbalance in smc_rx_splice smc_rx_splice() passes pages to splice_to_pipe() before taking the references that cover the lifetime of each splice entry. In the VM-backed RMB path, splice_to_pipe() may drop unqueued entries through smc_rx_spd_release(), while queued entries are released later via the pipe buffer callback. The old post-splice accounting also derives the number of queued VM pages from an offset mutated while building the descriptor, and a multi-page splice pairs one sock_hold() with multiple sock_put() calls. Take the page and socket references for every candidate entry before splice_to_pipe(), and drop the matching private state, page reference, and socket reference from smc_rx_spd_release() for entries that never get queued. This fixes a refcount imbalance that can underflow page refcounts and trigger a use-after-free. Added Reference https://git.kernel.org/stable/c/0b7d54cedea5cb158e21925ae0c6c2f5c87ed2a0 Added Reference https://git.kernel.org/stable/c/4515c78f4d9fd577270f012efeb062ea58b3682d Added Reference https://git.kernel.org/stable/c/5d9686af2976741bbd79b150d1c9e60b81e7f12e Added Reference https://git.kernel.org/stable/c/af02c67ce654356c58db20a0bb2db33ace3b07a8 Added Reference https://git.kernel.org/stable/c/c841789e456ec6751342fa800639ce8e82ff0e6b Added Reference https://git.kernel.org/stable/c/ca8342b5fc24c249fdb998468f6a168b457c67e5