In the Linux kernel, the following vulnerability has been resolved:
sched: act_ct: take care of padding in struct zones_ht_key
Blamed commit increased lookup key size from 2 bytes to 16 bytes,
because zones_ht_key got a struct net pointer.
Make sure rhashtable_lookup() is not using the padding bytes
which are not initialized.
BUG: KMSAN: uninit-value in rht_ptr_rcu include/linux/rhashtable.h:376 [inline]
BUG: KMSAN: uninit-value in __rhashtable_lookup include/linux/rhashtable.h:607 [inline]
BUG: KMSAN: uninit-value in rhashtable_lookup include/linux/rhashtable.h:646 [inline]
BUG: KMSAN: uninit-value in rhashtable_lookup_fast include/linux/rhashtable.h:672 [inline]
BUG: KMSAN: uninit-value in tcf_ct_flow_table_get+0x611/0x2260 net/sched/act_ct.c:329
rht_ptr_rcu include/linux/rhashtable.h:376 [inline]
__rhashtable_lookup include/linux/rhashtable.h:607 [inline]
rhashtable_lookup include/linux/rhashtable.h:646 [inline]
rhashtable_lookup_fast include/linux/rhashtable.h:672 [inline]
tcf_ct_flow_table_get+0x611/0x2260 net/sched/act_ct.c:329
tcf_ct_init+0xa67/0x2890 net/sched/act_ct.c:1408
tcf_action_init_1+0x6cc/0xb30 net/sched/act_api.c:1425
tcf_action_init+0x458/0xf00 net/sched/act_api.c:1488
tcf_action_add net/sched/act_api.c:2061 [inline]
tc_ctl_action+0x4be/0x19d0 net/sched/act_api.c:2118
rtnetlink_rcv_msg+0x12fc/0x1410 net/core/rtnetlink.c:6647
netlink_rcv_skb+0x375/0x650 net/netlink/af_netlink.c:2550
rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6665
netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
netlink_unicast+0xf52/0x1260 net/netlink/af_netlink.c:1357
netlink_sendmsg+0x10da/0x11e0 net/netlink/af_netlink.c:1901
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:745
____sys_sendmsg+0x877/0xb60 net/socket.c:2597
___sys_sendmsg+0x28d/0x3c0 net/socket.c:2651
__sys_sendmsg net/socket.c:2680 [inline]
__do_sys_sendmsg net/socket.c:2689 [inline]
__se_sys_sendmsg net/socket.c:2687 [inline]
__x64_sys_sendmsg+0x307/0x4a0 net/socket.c:2687
x64_sys_call+0x2dd6/0x3c10 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Local variable key created at:
tcf_ct_flow_table_get+0x4a/0x2260 net/sched/act_ct.c:324
tcf_ct_init+0xa67/0x2890 net/sched/act_ct.c:1408
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
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-25). 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, and whom BOD 26-04 binds: 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.
The score's inputs: 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