In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix use-after-free of iface in cifs_try_adding_channels()
cifs_try_adding_channels() iterates ses->iface_list with
list_for_each_entry_safe_from(), which captures the next entry
(niface) under iface_lock. The loop body then drops iface_lock for
the whole duration of cifs_ses_add_channel().
A concurrent interface refresh (SMB3_request_interfaces() ->
parse_server_interfaces()) marks all ifaces inactive and removes and
frees any that are not re-advertised via list_del() + kref_put(),
where release_iface() is a bare kfree(). Since niface typically has
no channel holding a reference, the list reference is its last and it
can be freed inside the unlocked window. On continue, the iterator
advance step then dereferences niface->iface_head.next, and the loop
body reads iface->rdma_capable/is_active, both on freed memory.
Fix this by never keeping an unreferenced list pointer across the
unlocked window. Each channel attempt now re-scans the list from the
head under iface_lock, takes a kref on the selected candidate, and
passes only that referenced candidate to cifs_ses_add_channel().
weight_fulfilled still tracks selection progress, so restarting the
scan preserves the original weighted distribution and the
weight_fulfilled-before-kref_put ordering on the failure path.
Add a per-pass attempts cap so a flapping interface refresh cannot
keep the inner loop spinning within a single tries increment.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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)14 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's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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