CVE-2026-99071
Received
Received - Intake
Linux Kernel Route Notification Race Condition
Vulnerability report for CVE-2026-99071, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-23
Last updated on: 2026-10-23
Assigner: kernel.org
Description
Description
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.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Linux | Linux | 680aea08e78c003292415518ad270bc20f9c80b1 |
| Linux | Linux | 680aea08e78c003292415518ad270bc20f9c80b1 |
| Linux | Linux | 680aea08e78c003292415518ad270bc20f9c80b1 |
| Linux | Linux | 680aea08e78c003292415518ad270bc20f9c80b1 |
| Linux | Linux | 680aea08e78c003292415518ad270bc20f9c80b1 |
| Linux | Linux | 5.12 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
