CVE-2026-98934 — ipv6: sr: use skb_get_hash_net() in seg6_make_flowlabel()
In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: use skb_get_hash_net() in seg6_make_flowlabel() Since commit d58e468b1112 ("flow_dissector: implements flow dissector BPF hook") __skb_flow_dissect() needs a net pointer, either from skb->dev, skb->sk, or since commit 3cbf4ffba5ee ("net: plumb network namespace into __skb_flow_dissect") a caller provided pointer. syzbot was able to reach seg6_make_flowlabel() with an skb having neither skb->dev nor skb->sk set: a TIPC UDP bearer sends a discovery message through an IPv4 route using seg6 encap, while net.ipv6.seg6_flowlabel is set to 1. seg6_make_flowlabel() already has a net pointer, use skb_get_hash_net(). WARNING: net/core/flow_dissector.c:1131 at __skb_flow_dissect+0x910/0x5368 net/core/flow_dissector.c:1126, CPU#0: syz.0.17/4930 Call trace: __skb_flow_dissect+0x910/0x5368 net/core/flow_dissector.c:1126 (P) __skb_get_hash_net+0xe0/0x29c net/core/flow_dissector.c:1903 skb_get_hash include/linux/skbuff.h:1663 [inline] seg6_make_flowlabel+0xcc/0x1ec net/ipv6/seg6_iptunnel.c:132 __seg6_do_srh_encap+0x320/0xbf4 net/ipv6/seg6_iptunnel.c:161 seg6_do_srh+0x4b4/0xa44 net/ipv6/seg6_iptunnel.c:431 seg6_output_core+0x164/0x688 net/ipv6/seg6_iptunnel.c:681 seg6_output+0x44/0x1ac net/ipv6/seg6_iptunnel.c:744 lwtunnel_output+0x3d0/0x664 net/core/lwtunnel.c:356 dst_output include/net/dst.h:470 [inline] ip_local_out+0x110/0x148 net/ipv4/ip_output.c:131 iptunnel_xmit+0x50c/0xd38 net/ipv4/ip_tunnel_core.c:97 udp_tunnel_xmit_skb+0x220/0x348 net/ipv4/udp_tunnel_core.c:187 tipc_udp_xmit+0x75c/0x9c0 net/tipc/udp_media.c:202 tipc_udp_send_msg+0x214/0x374 net/tipc/udp_media.c:274 tipc_bearer_xmit_skb+0x260/0x3b0 net/tipc/bearer.c:576 tipc_enable_bearer net/tipc/bearer.c:366 [inline] __tipc_nl_bearer_enable+0xc90/0xfb0 net/tipc/bearer.c:1048 tipc_nl_bearer_enable+0x2c/0x48 net/tipc/bearer.c:1057 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < 4ab37e4f4a33c64d9e565dc8c4c3ed774f05c0e3≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < 8fe3d6717f5536793727e60b7a0b7ec20c697def≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < 53b21bc2df6e8ed538bceda93a5104a5fe6a8a84≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < 086e8acb3a0e55f6d22d29fae2a4a3b1561bb766≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < 8ec454dcd00ce3375119111c6394964455b36d0dversion 4.20≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < de83419b5062a6f83bb9421be77cae734cbead65≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < 8407a2c1aa67c2a110a576df8f82a4e259188b82 and 1 more≥ d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9 and < a43d96620d080b1b2324a53e38dd7b4bff4825c1 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 24, 2026 → Oct 30, 2026 · 7 reading(s) · max 0.21%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 3× References added · Oct 23, 2026 – Oct 30, 2026
- 1× Official description updated · Oct 23, 2026 – Oct 23, 2026
References
10 on the record
- git.kernel.org/stable/c/4ab37e4f4a33c64d9e565dc8c4c3ed774f05c0e3
- nvd.nist.gov/vuln/detail/CVE-2026-98934
- git.kernel.org/stable/c/de83419b5062a6f83bb9421be77cae734cbead65
- git.kernel.org/stable/c/53b21bc2df6e8ed538bceda93a5104a5fe6a8a84
- git.kernel.org/stable/c/a43d96620d080b1b2324a53e38dd7b4bff4825c1
- git.kernel.org/stable/c/8407a2c1aa67c2a110a576df8f82a4e259188b82
- git.kernel.org/stable/c/8ec454dcd00ce3375119111c6394964455b36d0d
- git.kernel.org/stable/c/8fe3d6717f5536793727e60b7a0b7ec20c697def
- git.kernel.org/stable/c/086e8acb3a0e55f6d22d29fae2a4a3b1561bb766
- github.com/advisories/GHSA-646v-44w7-2g7c
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
- Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
- Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
- Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
- Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
- Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-98934 is "ipv6: sr: use skb_get_hash_net() in seg6_make_flowlabel()", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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