CVE Catalog

CVE-2026-64048

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.48%

39th percentile - higher than 39% of all known CVEs

Summary

In the Linux kernel's SMC-D subsystem, a vulnerability exists where a malicious peer can reply to an SMC-Dv2 proposal with CHID=0, matching an empty slot in the ism_dev[] array. This leads to a NULL pointer dereference in smc_conn_create(), causing a kernel panic.

Risk Assessment

An attacker can remotely trigger a kernel panic by sending a crafted ACCEPT response with CHID=0, causing service disruption and potential denial of service.

Recommendation

Apply the security patch for the Linux kernel that requires ism_dev[i] to be non-NULL before accepting a CHID match. Update to a kernel version containing this fix immediately.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS