Vulnerability in Linux

CVE-2026-89562

In the Linux kernel, the following vulnerability has been resolved: ip6_gre: fix hardware header length for NBMA tunnels ip6gre_tnl_link_config_route() accumulates the lower device's hardware header length into dev->hard_header_len whenever header_ops is set. This is incorrect for both users of header_ops. ip6gretap and ip6erspan have a fixed Ethernet hardware header length. For an NBMA ip6gre tunnel, ip6gre_header() creates only the GRE header, the optional FOU or GUE header, and the outer IPv6 header. The lower device header is headroom needed later, not part of the tunnel device's hardware header. Keep the lower device header in needed_headroom. Set hard_header_len to the tunnel header length only for ARPHRD_IP6GRE devices with header_ops, and leave the fixed Ethernet header length unchanged for tap and erspan devices.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.001 (2.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 3rd percentile — 2.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-89562: held from 0.002 to 0.001.

EPSS over last 30 days · oldest: 0.002 · newest: 0.001 · change: -0.000

Affected products

  • Linux — versions 187a6daf5db45adc807c85bbe285319107bed198, 5.10, cf3d9717a5271573fa193c4dfa0df856295d5b15

References

Frequently asked questions

What is CVE-2026-89562?
CVE-2026-89562 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2026-09-11.
How severe is CVE-2026-89562?
High severity. CVSS v3 base score is 7.8 out of 10.