In the Linux kernel, the following vulnerability has been resolved:
net: flow_dissector: use DEBUG_NET_WARN_ON_ONCE
The following splat is easy to reproduce upstream as well as in -stable
kernels. Florian Westphal provided the following commit:
d1dab4f71d37 ("net: add and use __skb_get_hash_symmetric_net")
but this complementary fix has been also suggested by Willem de Bruijn
and it can be easily backported to -stable kernel which consists in
using DEBUG_NET_WARN_ON_ONCE instead to silence the following splat
given __skb_get_hash() is used by the nftables tracing infrastructure to
to identify packets in traces.
[69133.561393] ------------[ cut here ]------------
[69133.561404] WARNING: CPU: 0 PID: 43576 at net/core/flow_dissector.c:1104 __skb_flow_dissect+0x134f/
[...]
[69133.561944] CPU: 0 PID: 43576 Comm: socat Not tainted 6.10.0-rc7+ #379
[69133.561959] RIP: 0010:__skb_flow_dissect+0x134f/0x2ad0
[69133.561970] Code: 83 f9 04 0f 84 b3 00 00 00 45 85 c9 0f 84 aa 00 00 00 41 83 f9 02 0f 84 81 fc ff
ff 44 0f b7 b4 24 80 00 00 00 e9 8b f9 ff ff <0f> 0b e9 20 f3 ff ff 41 f6 c6 20 0f 84 e4 ef ff ff 48 8d 7b 12 e8
[69133.561979] RSP: 0018:ffffc90000006fc0 EFLAGS: 00010246
[69133.561988] RAX: 0000000000000000 RBX: ffffffff82f33e20 RCX: ffffffff81ab7e19
[69133.561994] RDX: dffffc0000000000 RSI: ffffc90000007388 RDI: ffff888103a1b418
[69133.562001] RBP: ffffc90000007310 R08: 0000000000000000 R09: 0000000000000000
[69133.562007] R10: ffffc90000007388 R11: ffffffff810cface R12: ffff888103a1b400
[69133.562013] R13: 0000000000000000 R14: ffffffff82f33e2a R15: ffffffff82f33e28
[69133.562020] FS: 00007f40f7131740(0000) GS:ffff888390800000(0000) knlGS:0000000000000000
[69133.562027] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[69133.562033] CR2: 00007f40f7346ee0 CR3: 000000015d200001 CR4: 00000000001706f0
[69133.562040] Call Trace:
[69133.562044]
[69133.562049] ? __warn+0x9f/0x1a0
[ 1211.841384] ? __skb_flow_dissect+0x107e/0x2860
[...]
[ 1211.841496] ? bpf_flow_dissect+0x160/0x160
[ 1211.841753] __skb_get_hash+0x97/0x280
[ 1211.841765] ? __skb_get_hash_symmetric+0x230/0x230
[ 1211.841776] ? mod_find+0xbf/0xe0
[ 1211.841786] ? get_stack_info_noinstr+0x12/0xe0
[ 1211.841798] ? bpf_ksym_find+0x56/0xe0
[ 1211.841807] ? __rcu_read_unlock+0x2a/0x70
[ 1211.841819] nft_trace_init+0x1b9/0x1c0 [nf_tables]
[ 1211.841895] ? nft_trace_notify+0x830/0x830 [nf_tables]
[ 1211.841964] ? get_stack_info+0x2b/0x80
[ 1211.841975] ? nft_do_chain_arp+0x80/0x80 [nf_tables]
[ 1211.842044] nft_do_chain+0x79c/0x850 [nf_tables]
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