CVE-2021-1048: 
Linux Kernel vulnerability analysis and mitigation

A use-after-free vulnerability (CVE-2021-1048) was discovered in the eploopcheck_proc function of eventpoll.c in the Android kernel. The vulnerability was disclosed in November 2021 and affects Android operating systems and various Linux distributions. This security flaw requires no additional execution privileges or user interaction for exploitation (NVD, CVE Mitre).

The vulnerability is classified as a use-after-free issue in the kernel's eventpoll.c file, specifically in the eploopcheck_proc function. The CVSS v3.1 base score is 7.8, with attack vector being Local, attack complexity Low, and privileges required Low. The scope is Unchanged, while impact metrics for Confidentiality, Integrity, and Availability are all rated as High (Oracle Bulletin).

The vulnerability can lead to memory corruption and local privilege escalation, potentially allowing attackers to gain elevated system access. The high severity ratings for confidentiality, integrity, and availability indicate that successful exploitation could result in significant system compromise (NVD, Oracle Bulletin).

The vulnerability was patched in Linux kernel version 5.9-rc4. Various distributions have released fixes, including Debian which patched it in versions 5.10.223-1 for bullseye, 6.1.129-1 for bookworm, and 6.12.17-1 for sid/trixie (Debian Tracker).

Google addressed this vulnerability as part of their November 2021 security bulletin, marking it as one of six zero-day vulnerabilities patched in Android during that year. The security community noted its significance as it was being actively exploited in targeted attacks (Hacker News).