CVE-2024-42283: net: nexthop: Initialize all fields in dumped nexthops

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-08-17 · updated 2026-10-15
Weakness: CWE-908

Description

In the Linux kernel, the following vulnerability has been resolved: net: nexthop: Initialize all fields in dumped nexthops struct nexthop_grp contains two reserved fields that are not initialized by nla_put_nh_group(), and carry garbage. This can be observed e.g. with strace (edited for clarity): # ip nexthop add id 1 dev lo # ip nexthop add id 101 group 1 # strace -e recvmsg ip nexthop get id 101 ... recvmsg(... [{nla_len=12, nla_type=NHA_GROUP}, [{id=1, weight=0, resvd1=0x69, resvd2=0x67}]] ...) = 52 The fields are reserved and therefore not currently used. But as they are, they leak kernel memory, and the fact they are not just zero complicates repurposing of the fields for new ends. Initialize the full structure.

Affected products

Linux kernel: from 5.3 before 5.4.282; from 5.5 before 5.10.224; from 5.11 before 5.15.165; from 5.16 before 6.1.103; from 6.2 before 6.6.44; from 6.7 before 6.10.3 — fixed in 5.10.224, 5.15.165, 5.4.282, 6.1.103, 6.10.3, 6.6.44

How to fix

Upgrade to a fixed version: Linux kernel 5.10.224, 5.15.165, 5.4.282, 6.1.103. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2024-42283 or the next vulnerability affects your stack