CISA Warns of Actively Exploited Linux Kernel Vulnerability (CVE-2026-46300)

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has issued a warning regarding a Linux kernel vulnerability (CVE-2026-46300) that is actively being exploited by attackers to gain control of affected systems. The flaw, which affects how the Linux kernel combines network data, was added to CISA's Known Exploited Vulnerabilities catalog on October 28, 2026, with a remediation deadline of October 31, 2026. Attackers can chain this flaw with other vulnerabilities (CVE-2026-109618 and CVE-2026-109619) to implant PHP webshells and execute commands as root.