CVE-2026-98345 wifi: cfg80211: check IP header size in cfg80211_classify8021d()
A missing IP header size check in the Linux kernel Wi-Fi subsystem allows reading uninitialized memory, potentially disclosing sensitive kernel data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98345?
CVE-2026-98345 is a vulnerability in Linux, published on 6 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: check IP header size in cfg80211_classify8021d()
A frame that looks like IP can be transmitted, but be too short, so the DS field is read incorrectly:
BUG: KMSAN: uninit-value in cfg80211_classify8021d+0x99d/0x12b0 net/wireless/util.c:1027 cfg80211_classify8021d+0x99d/0x12b0 net/wireless/util.c:1027 ieee80211_select_queue+0x37a/0x9e0 net/mac80211/wme.c:180 __ieee80211_subif_start_xmit+0x60f/0x1d90 net/mac80211/tx.c:4304 ieee80211_subif_start_xmit+0xa8/0x6d0 net/mac80211/tx.c:4538 ... packet_sendmsg+0x9173/0xa2a0 net/packet/af_packet.c:3108
Use skb_header_pointer() like the MPLS case.
Which versions are affected by CVE-2026-98345?
How do I fix CVE-2026-98345?
Apply the vendor's patch.
Is CVE-2026-98345 being exploited?
There is no known exploitation of CVE-2026-98345 in the wild and no public exploit code.
Sources
Also known as AZL-105990, BELL-CVE-2026-98345, DEBIAN-CVE-2026-98345, GHSA-vm8v-8wgx-pm6r, UBUNTU-CVE-2026-98345.