CVE-2026-31685
In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_eui64: reject invalid MAC header for all packets `eui64_mt6()` derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_eui64: reject invalid MAC header for all packets `eui64_mt6()` derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the IPv6 source address. The existing guard only rejects an invalid MAC header when `par->fragoff != 0`. For packets with `par->fragoff == 0`, `eui64_mt6()` can still reach `eth_hdr(skb)` even when the MAC header is not valid. Fix this by removing the `par->fragoff != 0` condition so that packets with an invalid MAC header are rejected before accessing `eth_hdr(skb)`.
- CVSS 3.1
- 9.4 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H
- EPSS
- 0.34% probability · 27th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/288138418bef956f8b295751a4536c60f0e89f4aPatch
- https://git.kernel.org/stable/c/309ae3e9a51a69699ca94eac5fac5688fa562d55Patch
- https://git.kernel.org/stable/c/4d75bc2cd093bf5803edf512c099bfb220fd6459
- https://git.kernel.org/stable/c/7d6a57411caf54df025860c9b1a82cd42d57a562
- https://git.kernel.org/stable/c/807d6ee15804df6f01a35c910f09612e858739a6Patch
- https://git.kernel.org/stable/c/9eda5478746ef7dc0e4e537b5a5e4b0ca1027091Patch
- https://git.kernel.org/stable/c/d5603591373441fecf9951833d6d873e09320f08
- https://git.kernel.org/stable/c/fdce0b3590f724540795b874b4c8850c90e6b0a8Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.