CVE-2026-74479
net: pktgen: fix proc entry use-after-free
Description
In the Linux kernel, the following vulnerability has been resolved: net: pktgen: fix proc entry use-after-free pktgen_change_name() replaces pkt_dev->entry while holding t->if_lock. pktgen_remove_device() removes the same entry before _rem_dev_from_if_list() takes that lock. This allows the following interleaving: CPU 0 (NETDEV_CHANGENAME) CPU 1 (kpktgend) if_lock(t) proc_remove(pkt_dev->entry) proc_remove(pkt_dev->entry) pkt_dev->entry = proc_create_data(...) if_unlock(t) The kthread can pass the stale proc_dir_entry to proc_remove() after the rename path has freed it. A reproducer with a widened race window reports: BUG: KASAN: slab-use-after-free in proc_remove+0x78/0x80 Read of size 8 at addr ffff8881478fea70 by task kpktgend_0/67 Call Trace: proc_remove+0x78/0x80 pktgen_remove_device.isra.0+0x11c/0x4c0 pktgen_thread_worker+0x1214/0x6bc0 kthread+0x2c6/0x3b0 Allocated by task 95: __proc_create+0x204/0x790 proc_create_data+0x72/0xe0 pktgen_thread_write+0xd61/0x1510 Freed by task 28: kmem_cache_free+0xcb/0x3d0 proc_free_inode+0x5b/0x80 rcu_core+0x50a/0x1850 The buggy address belongs to the object at ffff8881478fea00 which belongs to the cache proc_dir_entry of size 192 Move proc_remove() into the if_lock-protected list removal helper. Keep it before list_del_rcu() to preserve the ordering required by add_device(). The rename path must then finish replacing the entry before removal, or it observes that the device is no longer on the list.
INFO
Published Date :
Aug. 15, 2026, 1:17 p.m.
Last Modified :
Aug. 15, 2026, 1:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-74479
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
- Move proc_remove() inside the if_lock.
- Ensure entry replacement before removal.
- Update the Linux kernel.
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-2026-74479.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74479 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-2026-74479
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-2026-74479 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74479 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. 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': '39df232f1a9ba48d41c68ee7d4046756e709cf91', 'lessThan': '4ef801b838d85c0ea5852c50667f7344ce3b6cd0', 'versionType': 'git'}, {'status': 'affected', 'version': '39df232f1a9ba48d41c68ee7d4046756e709cf91', 'lessThan': 'b006a5404470bd3eb2aa0425fc447183032047ef', 'versionType': 'git'}, {'status': 'affected', 'version': '39df232f1a9ba48d41c68ee7d4046756e709cf91', 'lessThan': '817ff6efdb7f484ea547218e11e17d8e43daa3b4', 'versionType': 'git'}], 'programFiles': ['net/core/pktgen.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '2.6.22'}, {'status': 'unaffected', 'version': '0', 'lessThan': '2.6.22', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc6', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/core/pktgen.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net: pktgen: fix proc entry use-after-free pktgen_change_name() replaces pkt_dev->entry while holding t->if_lock. pktgen_remove_device() removes the same entry before _rem_dev_from_if_list() takes that lock. This allows the following interleaving: CPU 0 (NETDEV_CHANGENAME) CPU 1 (kpktgend) if_lock(t) proc_remove(pkt_dev->entry) proc_remove(pkt_dev->entry) pkt_dev->entry = proc_create_data(...) if_unlock(t) The kthread can pass the stale proc_dir_entry to proc_remove() after the rename path has freed it. A reproducer with a widened race window reports: BUG: KASAN: slab-use-after-free in proc_remove+0x78/0x80 Read of size 8 at addr ffff8881478fea70 by task kpktgend_0/67 Call Trace: proc_remove+0x78/0x80 pktgen_remove_device.isra.0+0x11c/0x4c0 pktgen_thread_worker+0x1214/0x6bc0 kthread+0x2c6/0x3b0 Allocated by task 95: __proc_create+0x204/0x790 proc_create_data+0x72/0xe0 pktgen_thread_write+0xd61/0x1510 Freed by task 28: kmem_cache_free+0xcb/0x3d0 proc_free_inode+0x5b/0x80 rcu_core+0x50a/0x1850 The buggy address belongs to the object at ffff8881478fea00 which belongs to the cache proc_dir_entry of size 192 Move proc_remove() into the if_lock-protected list removal helper. Keep it before list_del_rcu() to preserve the ordering required by add_device(). The rename path must then finish replacing the entry before removal, or it observes that the device is no longer on the list. Added Reference https://git.kernel.org/stable/c/4ef801b838d85c0ea5852c50667f7344ce3b6cd0 Added Reference https://git.kernel.org/stable/c/817ff6efdb7f484ea547218e11e17d8e43daa3b4 Added Reference https://git.kernel.org/stable/c/b006a5404470bd3eb2aa0425fc447183032047ef