Critical vulnerabilities discovered in Bifrost AI gateway and F5 BIG-IP

Two significant cybersecurity vulnerabilities have been identified in widely used software.

A critical unauthenticated remote code execution vulnerability (CVE-2026-90898) affects all versions of the open-source AI gateway Bifrost prior to 2.1.0. The flaw, rated 9.8 on the CVSS scale, stems from management authentication being disabled by default. An attacker can execute arbitrary commands via a single HTTP request by registering a specific MCP client. A second flaw (CVE-2026-86242) allows arbitrary code execution through custom plugin registration on dynamically linked builds. Operators are urged to upgrade to version 2.1.0 or enable authentication.

Separately, F5 has disclosed a critical zero-day vulnerability (CVE-2026-94127) in its BIG-IP Access Policy Manager (APM) that is currently being exploited in the wild. The heap-based buffer overflow allows unauthenticated attackers to execute arbitrary code by sending specially crafted traffic to an affected OAuth configuration. The vulnerability is rated 9.8 on the CVSS v3.1 scale. CISA has added the flaw to its Known Exploited Vulnerabilities catalog, requiring U.S. federal civilian agencies to remediate the issue by September 25, 2026.