CVE-2023-42753: Kernel: netfilter: potential slab-out-of-bound access due to integer underflow
An array indexing vulnerability was found in the netfilter subsystem of the Linux kernel. A missing macro could lead to a miscalculation of the h->nets array offset, providing attackers with the primitive to arbitrarily increment/decrement a memory buffer out-of-bound. This issue may allow a local user to crash the system or potentially escalate their privileges on the system.
Other sources
Linux Kernel could allow a local authenticated attacker to execute arbitrary code on the system, caused by an integer underflow due to an array indexing issue in the netfilter ipset subsystem. By sending a specially crafted request, an attacker could exploit this vulnerability to execute arbitrary code or cause a denial of service condition.
— IBM
Potential slab-out-of-bound access due to integer underflow due to a missing IPSETHASHWITHNET0 macro in ipsethashnetportnet, which leads it to use the wrong wrong CIDRPOS(c) macro for calulating array offsets.
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.223-1Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1 - Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 6.6 - Upgrade
Upgrade
Linux Kernel (netfilter ipset)to a version that resolves this vulnerability.Patch CVE-2023-42753 - Configuration
Ensure the missing IP_SET_HASH_WITH_NET0 macro is present in ip_set_hash_netportnet so it uses the correct CIDR_POS macro for array offset calculation, preventing slab out-of-bounds access due to integer underflow (CVE-2023-42753).
Linux Kernel (netfilter ipset) IP_SET_HASH_WITH_NET0 macro = enabled
Event History
Frequently Asked Questions
What is the severity of CVE-2023-42753?
CVE-2023-42753 has been categorized as a medium severity vulnerability.
How do I fix CVE-2023-42753?
To mitigate CVE-2023-42753, update the kernel to version 6.6 or later for affected systems.
What systems are affected by CVE-2023-42753?
CVE-2023-42753 impacts various versions of the Linux kernel and certain Red Hat and Debian distributions.
What type of vulnerability is CVE-2023-42753?
CVE-2023-42753 is an array indexing vulnerability within the netfilter subsystem of the Linux kernel.
What could an attacker exploit in CVE-2023-42753?
An attacker could exploit CVE-2023-42753 to perform arbitrary memory buffer out-of-bounds operations.