CVE-2026-53238 netlabel: validate unlabeled address and mask attribute lengths
A crafted Generic Netlink request in the Linux kernel could trigger an out-of-bounds read, potentially disclosing sensitive memory contents.
- 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-2026-53238?
CVE-2026-53238 is a medium-severity vulnerability in Linux kernel, published on 25 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
netlabel: validate unlabeled address and mask attribute lengths
netlbl_unlabel_addrinfo_get() used the address attribute length to determine whether the attribute data could be read as an IPv4 or IPv6 address, but did not independently validate the corresponding mask attribute length. A crafted Generic Netlink request could therefore provide a valid IPv4/IPv6 address attribute with a shorter mask attribute, which would later be read as a full struct in_addr or struct in6_addr.
NLA_BINARY policy lengths are maximum lengths by default, so use NLA_POLICY_EXACT_LEN() for the unlabeled IPv4/IPv6 address and mask attributes. This rejects short attributes during policy validation and also exposes the exact length requirements through policy introspection.
Which versions are affected by CVE-2026-53238?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53238?
Apply the vendor's patch.
Is CVE-2026-53238 being exploited?
There is no known exploitation of CVE-2026-53238 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-90873, BELL-CVE-2026-53238, DEBIAN-CVE-2026-53238, GHSA-5qwx-4q7j-hwm2, ROOT-OS-DEBIAN-11-CVE-2026-53238, ROOT-OS-DEBIAN-12-CVE-2026-53238 and 3 more.