In the Linux kernel, the following vulnerability has been resolved:
netlink: fix potential deadlock in netlink_set_err()
syzbot reported a possible deadlock in netlink_set_err() [1]
A similar issue was fixed in commit 1d482e666b8e ("netlink: disable IRQs
for netlink_lock_table()") in netlink_lock_table()
This patch adds IRQ safety to netlink_set_err() and __netlink_diag_dump()
which were not covered by cited commit.
[1]
WARNING: possible irq lock inversion dependency detected
6.4.0-rc6-syzkaller-00240-g4e9f0ec38852 #0 Not tainted
syz-executor.2/23011 just changed the state of lock:
ffffffff8e1a7a58 (nl_table_lock){.+.?}-{2:2}, at: netlink_set_err+0x2e/0x3a0 net/netlink/af_netlink.c:1612
but this lock was taken by another, SOFTIRQ-safe lock in the past:
(&local->queue_stop_reason_lock){..-.}-{2:2}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(nl_table_lock);
local_irq_disable();
lock(&local->queue_stop_reason_lock);
lock(nl_table_lock);
lock(&local->queue_stop_reason_lock);
* DEADLOCK *
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
- EG Severity
- Not assessed: no CVSS publishedA missing CVSS is not a severity of zero.
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-28). 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
- No SSVC decision: EchelonGraph has not assessed this CVECISA BOD 26-04: 14 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 BOD 26-04 block below.
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.
The score's inputs: 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