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7.8
HIGH CVSS 3.1
CVE-2026-68284
bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg()
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg() tcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which drops and reacquires the socket lock. Its error path tries to decide whether msg_tx names the local temporary message by comparing it with the current value of psock->cork. This comparison is unsafe when two threads send on the same socket: Thread A Thread B msg_tx = psock->cork sk_msg_alloc() fails sk_stream_wait_memory() releases the socket lock acquires the socket lock completes the cork psock->cork = NULL frees the cork reacquires the socket lock msg_tx != psock->cork sk_msg_free(msg_tx) The stale cork is therefore mistaken for the local temporary message and freed again. KASAN reported: BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50 Read of size 4 at addr ffff88810c908800 by task poc/90 Call Trace: sk_msg_free+0x49/0x50 tcp_bpf_sendmsg+0x14f5/0x1cc0 __sys_sendto+0x32c/0x3a0 __x64_sys_sendto+0xdb/0x1b0 Allocated by task 89: __kasan_kmalloc+0x8f/0xa0 tcp_bpf_sendmsg+0x16b3/0x1cc0 Freed by task 91: __kasan_slab_free+0x43/0x70 kfree+0x131/0x3c0 tcp_bpf_sendmsg+0xec3/0x1cc0 msg_tx can only name the stack-local tmp or the shared cork. Check for tmp directly so a changed psock->cork cannot turn a shared message into an apparent local one.

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-2026-68284 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
Fix a use-after-free vulnerability in tcp_bpf_sendmsg by checking the message directly.
  • Apply the kernel patch for the described race condition.
  • Update the Linux kernel to a patched version.
  • Verify the socket lock handling in concurrent sends.
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-2026-68284.

URL Resource
https://git.kernel.org/stable/c/2d66a033864e27ab8d5e44cb36f31d9d2413bee4
https://git.kernel.org/stable/c/752b1159ed5d0c48fe169a3721b96660a9822aa1
https://git.kernel.org/stable/c/786d690257ec7a0c839f8710456e444ce3f1348b
https://git.kernel.org/stable/c/cde4d6bcd9b73073c66498f6723c7b364c4dbc18
https://git.kernel.org/stable/c/ee762f684eefa59de34d9ed93cab08336e834f47
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-68284 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-2026-68284 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-2026-68284 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-2026-68284 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': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': 'ee762f684eefa59de34d9ed93cab08336e834f47', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': 'cde4d6bcd9b73073c66498f6723c7b364c4dbc18', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '786d690257ec7a0c839f8710456e444ce3f1348b', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '752b1159ed5d0c48fe169a3721b96660a9822aa1', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '2d66a033864e27ab8d5e44cb36f31d9d2413bee4', 'versionType': 'git'}], 'programFiles': ['net/ipv4/tcp_bpf.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.20'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.20', '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/ipv4/tcp_bpf.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': 'ee762f684eefa59de34d9ed93cab08336e834f47', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': 'cde4d6bcd9b73073c66498f6723c7b364c4dbc18', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '786d690257ec7a0c839f8710456e444ce3f1348b', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '752b1159ed5d0c48fe169a3721b96660a9822aa1', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '2d66a033864e27ab8d5e44cb36f31d9d2413bee4', 'versionType': 'git'}], 'programFiles': ['net/ipv4/tcp_bpf.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.20'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.20', '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/ipv4/tcp_bpf.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': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': 'ee762f684eefa59de34d9ed93cab08336e834f47', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': 'cde4d6bcd9b73073c66498f6723c7b364c4dbc18', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '786d690257ec7a0c839f8710456e444ce3f1348b', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '752b1159ed5d0c48fe169a3721b96660a9822aa1', 'versionType': 'git'}, {'status': 'affected', 'version': '604326b41a6fb9b4a78b6179335decee0365cd8c', 'lessThan': '2d66a033864e27ab8d5e44cb36f31d9d2413bee4', 'versionType': 'git'}], 'programFiles': ['net/ipv4/tcp_bpf.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.20'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.20', '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/ipv4/tcp_bpf.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg() tcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which drops and reacquires the socket lock. Its error path tries to decide whether msg_tx names the local temporary message by comparing it with the current value of psock->cork. This comparison is unsafe when two threads send on the same socket: Thread A Thread B msg_tx = psock->cork sk_msg_alloc() fails sk_stream_wait_memory() releases the socket lock acquires the socket lock completes the cork psock->cork = NULL frees the cork reacquires the socket lock msg_tx != psock->cork sk_msg_free(msg_tx) The stale cork is therefore mistaken for the local temporary message and freed again. KASAN reported: BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50 Read of size 4 at addr ffff88810c908800 by task poc/90 Call Trace: sk_msg_free+0x49/0x50 tcp_bpf_sendmsg+0x14f5/0x1cc0 __sys_sendto+0x32c/0x3a0 __x64_sys_sendto+0xdb/0x1b0 Allocated by task 89: __kasan_kmalloc+0x8f/0xa0 tcp_bpf_sendmsg+0x16b3/0x1cc0 Freed by task 91: __kasan_slab_free+0x43/0x70 kfree+0x131/0x3c0 tcp_bpf_sendmsg+0xec3/0x1cc0 msg_tx can only name the stack-local tmp or the shared cork. Check for tmp directly so a changed psock->cork cannot turn a shared message into an apparent local one.
    Added Reference https://git.kernel.org/stable/c/2d66a033864e27ab8d5e44cb36f31d9d2413bee4
    Added Reference https://git.kernel.org/stable/c/752b1159ed5d0c48fe169a3721b96660a9822aa1
    Added Reference https://git.kernel.org/stable/c/786d690257ec7a0c839f8710456e444ce3f1348b
    Added Reference https://git.kernel.org/stable/c/cde4d6bcd9b73073c66498f6723c7b364c4dbc18
    Added Reference https://git.kernel.org/stable/c/ee762f684eefa59de34d9ed93cab08336e834f47
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
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