CVE-2026-99072
Received
Received - Intake
Heap-based Buffer Overflow in Linux Kernel
Vulnerability report for CVE-2026-99072, 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: stop route notification sizing when nexthop group shrinks
Commit 680aea08e78c ("net: ipv4: Emit notification when fib
hardware flags are changed") added an RCU-only fib_nlmsg_size() call
for asynchronous hardware flag notifications.
fib_nlmsg_size() checks fib_info_num_path() before each iteration,
then fib_info_nhc() independently reloads nh->nh_grp. If
RTM_NEWNEXTHOP replaces a group with fewer paths between those loads,
fib_info_nhc() returns NULL and fib_nexthop_nlmsg_size() dereferences
it.
Stop sizing when the indexed path is absent. Nexthop groups are
dense, so the current snapshot has no later path.
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 |
