CVE-2026-64048
net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot
Description
In the Linux kernel, the following vulnerability has been resolved: net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot On the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is reserved for an SMC-Dv1 device. smc_find_ism_v2_device_clnt() populates V2 entries starting at index 1, so when no V1 device is selected slot 0 is left in its kzalloc()'ed state with ism_dev[0] == NULL and ism_chid[0] == 0. smc_v2_determine_accepted_chid() then matches the peer's CHID against the array starting from index 0 using the CHID alone. A malicious peer replying to a SMC-Dv2-only proposal with d1.chid == 0 matches the empty slot, ini->ism_selected becomes 0, and the subsequent ism_dev[0]->lgr_lock dereference in smc_conn_create() faults at offsetof(struct smcd_dev, lgr_lock) == 0x68: BUG: KASAN: null-ptr-deref in _raw_spin_lock_bh+0x79/0xe0 Write of size 4 at addr 0000000000000068 by task exploit/144 Call Trace: _raw_spin_lock_bh smc_conn_create (net/smc/smc_core.c:1997) __smc_connect (net/smc/af_smc.c:1447) smc_connect (net/smc/af_smc.c:1720) __sys_connect __x64_sys_connect do_syscall_64 Require ism_dev[i] to be non-NULL before accepting a CHID match.
INFO
Published Date :
July 19, 2026, 4:17 p.m.
Last Modified :
July 20, 2026, 3:17 p.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-64048
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
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel to include the fix.
- Ensure ism_dev entries are not NULL before CHID matches.
- Apply the specific patch for the net/smc component.
- Test the system after applying the update.
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-2026-64048.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64048 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-2026-64048
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-2026-64048 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64048 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
Jul. 20, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 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': 'a7c9c5f4af7f6098da68705fc5d86565d0728ef7', 'lessThan': '6927cacf2b10d4fa80c1a2d407512ef9397c59c6', 'versionType': 'git'}, {'status': 'affected', 'version': 'a7c9c5f4af7f6098da68705fc5d86565d0728ef7', 'lessThan': 'd38ba387244e5c5f7db3e11ea98bc2c7beccb0c0', 'versionType': 'git'}, {'status': 'affected', 'version': 'a7c9c5f4af7f6098da68705fc5d86565d0728ef7', 'lessThan': '53eb7bd09aace72fa17510d80e0caf5ca058c231', 'versionType': 'git'}, {'status': 'affected', 'version': 'a7c9c5f4af7f6098da68705fc5d86565d0728ef7', 'lessThan': 'afa9036b8c9963947b487c36e332df6a42c96fcb', 'versionType': 'git'}, {'status': 'affected', 'version': 'a7c9c5f4af7f6098da68705fc5d86565d0728ef7', 'lessThan': '65edb3b0822cfe5041be8fbabebd57e2e5ad9f4e', 'versionType': 'git'}, {'status': 'affected', 'version': 'a7c9c5f4af7f6098da68705fc5d86565d0728ef7', 'lessThan': '277740023def559a4a2ddc3e8e784ee37a0f16a9', 'versionType': 'git'}], 'programFiles': ['net/smc/af_smc.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.10'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.10', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.1.175', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.142', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.92', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.34', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.11', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/smc/af_smc.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot On the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is reserved for an SMC-Dv1 device. smc_find_ism_v2_device_clnt() populates V2 entries starting at index 1, so when no V1 device is selected slot 0 is left in its kzalloc()'ed state with ism_dev[0] == NULL and ism_chid[0] == 0. smc_v2_determine_accepted_chid() then matches the peer's CHID against the array starting from index 0 using the CHID alone. A malicious peer replying to a SMC-Dv2-only proposal with d1.chid == 0 matches the empty slot, ini->ism_selected becomes 0, and the subsequent ism_dev[0]->lgr_lock dereference in smc_conn_create() faults at offsetof(struct smcd_dev, lgr_lock) == 0x68: BUG: KASAN: null-ptr-deref in _raw_spin_lock_bh+0x79/0xe0 Write of size 4 at addr 0000000000000068 by task exploit/144 Call Trace: _raw_spin_lock_bh smc_conn_create (net/smc/smc_core.c:1997) __smc_connect (net/smc/af_smc.c:1447) smc_connect (net/smc/af_smc.c:1720) __sys_connect __x64_sys_connect do_syscall_64 Require ism_dev[i] to be non-NULL before accepting a CHID match. Added Reference https://git.kernel.org/stable/c/277740023def559a4a2ddc3e8e784ee37a0f16a9 Added Reference https://git.kernel.org/stable/c/53eb7bd09aace72fa17510d80e0caf5ca058c231 Added Reference https://git.kernel.org/stable/c/65edb3b0822cfe5041be8fbabebd57e2e5ad9f4e Added Reference https://git.kernel.org/stable/c/6927cacf2b10d4fa80c1a2d407512ef9397c59c6 Added Reference https://git.kernel.org/stable/c/afa9036b8c9963947b487c36e332df6a42c96fcb Added Reference https://git.kernel.org/stable/c/d38ba387244e5c5f7db3e11ea98bc2c7beccb0c0