In the Linux kernel, the following vulnerability has been resolved:
tipc: fix kernel warning when sending SYN message
When sending a SYN message, this kernel stack trace is observed:
...
[ 13.396352] RIP: 0010:_copy_from_iter+0xb4/0x550
...
[ 13.398494] Call Trace:
[ 13.398630]
[ 13.398630] ? __alloc_skb+0xed/0x1a0
[ 13.398630] tipc_msg_build+0x12c/0x670 [tipc]
[ 13.398630] ? shmem_add_to_page_cache.isra.71+0x151/0x290
[ 13.398630] __tipc_sendmsg+0x2d1/0x710 [tipc]
[ 13.398630] ? tipc_connect+0x1d9/0x230 [tipc]
[ 13.398630] ? __local_bh_enable_ip+0x37/0x80
[ 13.398630] tipc_connect+0x1d9/0x230 [tipc]
[ 13.398630] ? __sys_connect+0x9f/0xd0
[ 13.398630] __sys_connect+0x9f/0xd0
[ 13.398630] ? preempt_count_add+0x4d/0xa0
[ 13.398630] ? fpregs_assert_state_consistent+0x22/0x50
[ 13.398630] __x64_sys_connect+0x16/0x20
[ 13.398630] do_syscall_64+0x42/0x90
[ 13.398630] entry_SYSCALL_64_after_hwframe+0x63/0xcd
It is because commit a41dad905e5a ("iov_iter: saner checks for attempt
to copy to/from iterator") has introduced sanity check for copying
from/to iov iterator. Lacking of copy direction from the iterator
viewpoint would lead to kernel stack trace like above.
This commit fixes this issue by initializing the iov iterator with
the correct copy direction when sending SYN or ACK without data.
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