CVE-2023-31248 Linux Kernel nftables Use-After-Free Local Privilege Escalation Vulnerability
A use-after-free in Linux Kernel nftables allows local attackers to escalate privileges by exploiting missing active chain checks.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-31248?
CVE-2023-31248 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 5 Jul 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Linux Kernel nftables Use-After-Free Local Privilege Escalation Vulnerability; `nft_chain_lookup_byid()` failed to check whether a chain was active and CAP_NET_ADMIN is in any user or network namespace
Weakness: CWE-416
Which versions are affected by CVE-2023-31248?
It affects 4 products.
Products include Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Linux kernel.
How do I fix CVE-2023-31248?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2023-31248 being exploited?
There is no known exploitation of CVE-2023-31248 in the wild and no public exploit code.
Other vulnerabilities in Canonical Ubuntu Linux
Sources
Also known as DEBIAN-CVE-2023-31248, GHSA-vr3g-637q-4rh6, UBUNTU-CVE-2023-31248.