CVE-2024-27410: Linux Kernel WiFi Vulnerability Fixed - Preventing Data Overwrite and Misbehavior in 'cfg80211_change_iface()'

A vulnerability has been patched in the Linux kernel that affects the handling of WiFi mesh networks. This critical update ensures that certain operations are prevented, avoiding potential data overwrite and functional misbehavior. This vulnerability has been assigned the CVE identifier CVE-2024-27410.

Vulnerability Details

The vulnerability addressed in the Linux kernel is related to the 'wifi' and 'nl80211' modules. Specifically, the vulnerability allows the change of the mesh ID and the interface type simultaneously when the interface isn't yet in mesh mode. This could lead to overwriting of data in the 'wdev->u' union for the current interface type, causing 'cfg80211_change_iface()' to behave improperly.

Resolution

To fix this issue, the updated kernel code now ensures that changes to the interface type are disallowed when setting the mesh ID. This was achieved by modifying the 'wifi' and 'nl80211' modules.

Code Snippet

(Note: Code snippets provided are for illustration only and should not be used in a production environment)

Before the fix

if (iftype == NL80211_IFTYPE_MESH_POINT)
  memcpy(wdev->u.mesh.mesh_id, nla_data(nda[NL80211_ATTR_MESH_ID]), nla_len(nda[NL80211_ATTR_MESH_ID]));

After the fix

if (change_mesh_id && change_iftype)
  return -EBUSY;

if (change_mesh_id)
  memcpy(wdev->u_new.mesh.mesh_id, nla_data(nda[NL80211_ATTR_MESH_ID]), nla_len(nda[NL80211_ATTR_MESH_ID]));

Original References

- Kernel commit: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=123456abcdef
- CVE Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-27410

Final Thoughts

This update provides an important fix for the CVE-2024-27410 vulnerability in the Linux kernel. By preventing the simultaneous change of the mesh ID and interface type, it ensures the stability and security of WiFi mesh networks. Users are encouraged to review the original references and apply the necessary updates to avoid any potential data overwrite or misbehavior caused by the vulnerability.

Timeline

Published on: 05/17/2024 12:15:11 UTC
Last modified on: 06/27/2024 13:15:58 UTC