CVE intelligence

CVE-2026-99071

Vulnerability intelligence

Published Oct 23, 2026Sources checked Oct 27, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-99071. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Oct 26, 2026

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-99071?

In the Linux kernel, the following vulnerability has been resolved:

ipv4: do not warn on route notification size race

Commit 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed") added asynchronous route notifications for hardware flag changes.

fib_alias_hw_flags_set() sizes the skb with fib_nlmsg_size() and later fills it with fib_dump_info() while holding only RCU. With nexthop compatibility mode enabled, a concurrent replacement can grow the group between these independent snapshots. fib_dump_info() can then legitimately return -EMSGSIZE, so the warning does not prove a sizing bug.

Remove the warning. The existing error path still frees the skb and reports the error to listeners.

Source: NVD