In the Linux kernel, the following vulnerability has been resolved:
nbd: always initialize struct msghdr completely
syzbot complains that msg->msg_get_inq value can be uninitialized [1]
struct msghdr got many new fields recently, we should always make
sure their values is zero by default.
[1]
BUG: KMSAN: uninit-value in tcp_recvmsg+0x686/0xac0 net/ipv4/tcp.c:2571
tcp_recvmsg+0x686/0xac0 net/ipv4/tcp.c:2571
inet_recvmsg+0x131/0x580 net/ipv4/af_inet.c:879
sock_recvmsg_nosec net/socket.c:1044 [inline]
sock_recvmsg+0x12b/0x1e0 net/socket.c:1066
__sock_xmit+0x236/0x5c0 drivers/block/nbd.c:538
nbd_read_reply drivers/block/nbd.c:732 [inline]
recv_work+0x262/0x3100 drivers/block/nbd.c:863
process_one_work kernel/workqueue.c:2627 [inline]
process_scheduled_works+0x104e/0x1e70 kernel/workqueue.c:2700
worker_thread+0xf45/0x1490 kernel/workqueue.c:2781
kthread+0x3ed/0x540 kernel/kthread.c:388
ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
Local variable msg created at:
__sock_xmit+0x4c/0x5c0 drivers/block/nbd.c:513
nbd_read_reply drivers/block/nbd.c:732 [inline]
recv_work+0x262/0x3100 drivers/block/nbd.c:863
CPU: 1 PID: 7465 Comm: kworker/u5:1 Not tainted 6.7.0-rc7-syzkaller-00041-gf016f7547aee #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: nbd5-recv recv_work
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (4.4): severity, escalated by confirmed exploitation. This CVE's 4.4 is its impact severity (EG Severity), not escalated.
- EG Severity
- 4.4 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 2026-10-17). 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