Use of uninitialized resource in Linux kernel - CVE-2026-63870
Published: July 20, 2026
Vulnerability identifier: #VU138792
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63870
CWE-ID: CWE-908
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use of uninitialized memory in lowpan_xmit() in the ieee802154 6LoWPAN transmit path when processing a non-IPv6 packet queued for transmission on a 6LoWPAN interface. A local user can queue a non-IPv6 packet for transmission to cause a denial of service.
The issue occurs because address information in skb headroom may remain uninitialized and is later copied and used by the transmit path.
Affected software
Linux kernel
How to mitigate CVE-2026-63870
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
External References
- https://git.kernel.org/stable/c/1a827b95e62b4cbe851ae7cc9c961cdfa769cca4
- https://git.kernel.org/stable/c/285b0842f2e01c3edf805f1fd64da11d9b7f6b4c
- https://git.kernel.org/stable/c/3150e6d3223dfc356308125cabf9c34169842d2a
- https://git.kernel.org/stable/c/3a5f3f7aff18bcc36a57839cf50cf0cc8de707f3
- https://git.kernel.org/stable/c/87172cc8dc49aaf54407a31edffb0232f8cb93ab
- https://git.kernel.org/stable/c/8da95cb6ad7d656c871e776a9c7b77e894d6d89c
- https://git.kernel.org/stable/c/af07fffbd53ddc3ec3c2a4ca914f27899fa89bca
- https://git.kernel.org/stable/c/c1819c8defa235c7beda859bc185b1c429a55ecd