CVE-2026-74719
net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()
Description
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler() The SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in smc_llc_event_handler() stores an incoming qentry into the local LLC flow without first checking whether a qentry is already pending. If a malicious or buggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is active and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the pointer without freeing the previous allocation, leaking one kmalloc-96 object per spurious message. The sibling SMC_LLC_DELETE_LINK branch already has the correct !flow->qentry guard. Apply the same guard to the CONFIRM_LINK/ADD_LINK_CONT branch so that a duplicate message when qentry is already occupied falls through to break and is freed by the kfree(qentry) at the out: label, rather than silently leaking the existing allocation. The response direction (smc_llc_rx_response()) is unaffected: it already guards with flow->qentry at the equivalent site and drops duplicate responses correctly.
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
Solution
- Apply the provided kernel patch.
- Ensure qentry checks are implemented correctly.
- Validate duplicate message handling.
- Free allocated memory to prevent leaks.
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-2026-74719.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74719 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-2026-74719
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).
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The following list is the news that have been mention
CVE-2026-74719 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74719 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': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': 'e384f3cba6ea709f5b2272b1770db4ce14047f78', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': 'a1e980d7a9e7ee6faf4f5fd7b450413b969af26d', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': 'e0eb87677c76b157cdf8eb7c1f19e56227165a33', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': '06734dfeaeba886aab1bf147249195b888ac3e4d', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': 'c23c409228629107203d3c3e95fff1473173f1a6', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': '10cb31b2b74cb664c6c95cf72364d7d5c483ab82', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': 'bfc336a9fbbf09805f3dfe25c195a4db90af2846', 'versionType': 'git'}, {'status': 'affected', 'version': '0fb0b02bd6fd26cba38002be4a6bbcae2228fd44', 'lessThan': '976245094925bab9bc39366b2e9ab44ffcde61d0', 'versionType': 'git'}], 'programFiles': ['net/smc/smc_llc.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.8'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.8', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.265', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.216', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'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_llc.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler() The SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in smc_llc_event_handler() stores an incoming qentry into the local LLC flow without first checking whether a qentry is already pending. If a malicious or buggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is active and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the pointer without freeing the previous allocation, leaking one kmalloc-96 object per spurious message. The sibling SMC_LLC_DELETE_LINK branch already has the correct !flow->qentry guard. Apply the same guard to the CONFIRM_LINK/ADD_LINK_CONT branch so that a duplicate message when qentry is already occupied falls through to break and is freed by the kfree(qentry) at the out: label, rather than silently leaking the existing allocation. The response direction (smc_llc_rx_response()) is unaffected: it already guards with flow->qentry at the equivalent site and drops duplicate responses correctly. Added Reference https://git.kernel.org/stable/c/06734dfeaeba886aab1bf147249195b888ac3e4d Added Reference https://git.kernel.org/stable/c/10cb31b2b74cb664c6c95cf72364d7d5c483ab82 Added Reference https://git.kernel.org/stable/c/976245094925bab9bc39366b2e9ab44ffcde61d0 Added Reference https://git.kernel.org/stable/c/a1e980d7a9e7ee6faf4f5fd7b450413b969af26d Added Reference https://git.kernel.org/stable/c/bfc336a9fbbf09805f3dfe25c195a4db90af2846 Added Reference https://git.kernel.org/stable/c/c23c409228629107203d3c3e95fff1473173f1a6 Added Reference https://git.kernel.org/stable/c/e0eb87677c76b157cdf8eb7c1f19e56227165a33 Added Reference https://git.kernel.org/stable/c/e384f3cba6ea709f5b2272b1770db4ce14047f78