CVE-2023-53495: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-53495 is an out-of-bounds write vulnerability in the Linux kernel's mvpp2 (Marvell Prestera PP2) Ethernet driver, specifically in the mvpp2_ethtool_get_rxnfc() function. The flaw arises because the rules buffer is allocated based on a user-supplied rule_cnt value that is not validated before use, enabling out-of-bounds writes or NULL pointer dereference. It affects Linux kernel versions 5.2 through 6.6-rc1 across multiple stable branches. The CVE was published on October 1, 2025, with NVD initial analysis completed January 16, 2026. It carries a CVSS v3.1 base score of 7.8 (High) (Feedly, kernel.org patches).

The root cause is classified as CWE-787 (Out-of-bounds Write). In mvpp2_ethtool_get_rxnfc(), the rules array is allocated by the kernel's ethtool_get_rxnfc() wrapper with a size derived from the user-space-supplied rule_cnt field, but the driver does not validate rule_cnt before indexing into the rules buffer. A local attacker with low privileges can invoke ethtool operations with a crafted rule_cnt value to trigger writes beyond the allocated buffer boundary or cause a NULL pointer dereference. The attack vector is local (AV:L), requires low privileges (PR:L), and no user interaction (UI:N) (Feedly).

Successful exploitation can result in kernel memory corruption, system crashes (denial of service), or privilege escalation to root on affected systems. The vulnerability affects confidentiality, integrity, and availability at a high level, as memory corruption in kernel space can be leveraged to overwrite security-sensitive structures. Systems running Linux kernel versions 5.2–6.6-rc1 on hardware using the Marvell Prestera PP2 (mvpp2) Ethernet driver are at risk (Feedly).

There is no public proof-of-concept exploit and no evidence of in-the-wild exploitation at this time. The EPSS score is approximately 0.024% (0.000240), indicating a very low probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. No threat actor attribution has been reported (Feedly).

Upgrade the Linux kernel to one of the patched stable versions: 5.4.257, 5.10.195, 5.15.132, 6.1.54, or 6.5.4 (and later). Patches are available in the upstream kernel stable git repository across multiple branches. As a temporary workaround, restrict access to ethtool operations to trusted, privileged users only (e.g., via capability restrictions or access controls), reducing the attack surface for local exploitation (Feedly, kernel.org patches).