In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix illegal rmb_desc access in SMC-D connection dump
A crash was found when dumping SMC-D connections. It can be reproduced
by following steps:
smc_run nginx
smc_run wrk -t 16 -c 1000 -d -H 'Connection: Close'
- continuously dump SMC-D connections in parallel:
watch -n 1 'smcss -D'
BUG: kernel NULL pointer dereference, address: 0000000000000030
CPU: 2 PID: 7204 Comm: smcss Kdump: loaded Tainted: G E 6.7.0+ #55
RIP: 0010:__smc_diag_dump.constprop.0+0x5e5/0x620 [smc_diag]
Call Trace:
? __die+0x24/0x70
? page_fault_oops+0x66/0x150
? exc_page_fault+0x69/0x140
? asm_exc_page_fault+0x26/0x30
? __smc_diag_dump.constprop.0+0x5e5/0x620 [smc_diag]
? __kmalloc_node_track_caller+0x35d/0x430
? __alloc_skb+0x77/0x170
smc_diag_dump_proto+0xd0/0xf0 [smc_diag]
smc_diag_dump+0x26/0x60 [smc_diag]
netlink_dump+0x19f/0x320
__netlink_dump_start+0x1dc/0x300
smc_diag_handler_dump+0x6a/0x80 [smc_diag]
? __pfx_smc_diag_dump+0x10/0x10 [smc_diag]
sock_diag_rcv_msg+0x121/0x140
? __pfx_sock_diag_rcv_msg+0x10/0x10
netlink_rcv_skb+0x5a/0x110
sock_diag_rcv+0x28/0x40
netlink_unicast+0x22a/0x330
netlink_sendmsg+0x1f8/0x420
__sock_sendmsg+0xb0/0xc0
____sys_sendmsg+0x24e/0x300
? copy_msghdr_from_user+0x62/0x80
___sys_sendmsg+0x7c/0xd0
? __do_fault+0x34/0x160
? do_read_fault+0x5f/0x100
? do_fault+0xb0/0x110
? __handle_mm_fault+0x2b0/0x6c0
__sys_sendmsg+0x4d/0x80
do_syscall_64+0x69/0x180
entry_SYSCALL_64_after_hwframe+0x6e/0x76
It is possible that the connection is in process of being established
when we dump it. Assumed that the connection has been registered in a
link group by smc_conn_create() but the rmb_desc has not yet been
initialized by smc_buf_create(), thus causing the illegal access to
conn->rmb_desc. So fix it by checking before dump.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-17). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it