CISA Adds Linux Kernel Frag Gap Flaw and Two Other Exploited Vulnerabilities to KEV Catalog
The US Cybersecurity and Infrastructure Security Agency (CISA) issued an alert on August 27, 2026, adding three actively exploited vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog and directing federal agencies to take immediate action.
Two of the vulnerabilities carry an August 30 remediation deadline: CVE-2026-53362 and CVE-2023-49105. The most detailed entry concerns CVE-2026-53362, a privilege-escalation flaw in the Linux kernel tracked under the alias Frag Gap.
The vulnerability resides in the IPv6 packet-generation code path, where an out-of-bounds memory write occurs. A low-privileged local user can leverage the flaw to escalate privileges to root. The Linux Kernel Organization scored the issue CVSS v3.1 7.8 and classified it as High severity. Public exploit code is already circulating.
CISA’s action requires US government agencies to apply available patches or mitigations within the stated timeframe, reflecting confirmed in-the-wild exploitation of all three vulnerabilities.
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