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F5 BIG-IP and related products Quarterly Security Notification (multiple vulnerabilities)

Security Patch Release
First reported
Last updated
Happening score
H score 34
1 unique sources, 1 articles

Summary

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F5's Quarterly Security Notification told customers to apply security updates for BIG-IP, F5OS, BIG-IP Next for Kubernetes, BIG-IQ and APM clients, making the bulletin a broad remediation step across multiple products. The guidance matters because stolen files included information about undisclosed vulnerabilities in BIG-IP. CISA also told federal agencies to apply updates from F5 and review whether management interfaces are exposed to the public internet.

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Advisory/Mitigation
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Timeline

  1. 16.10.2025 11:39 2 articles · 7mo ago

    F5 discloses nation-state breach and urges urgent patching

    Initial Disclosure

    F5 informed customers that a highly sophisticated nation-state threat actor had maintained long-term, persistent access to certain F5 systems and downloaded files from its BIG-IP product development environment and engineering knowledge management platforms after discovering the activity in August 2025. The stolen files included BIG-IP source code and information about undisclosed vulnerabilities, and F5 said it had no knowledge of active exploitation while urging customers to apply updates for BIG-IP, F5OS, BIG-IP Next for Kubernetes, BIG-IQ and APM clients, harden systems with the F5 iHealth Diagnostic Tool, enable BIG-IP event streaming to SIEM, and conduct proactive threat hunting. CISA also issued an emergency directive for federal agencies to check whether networked management interfaces are publicly exposed and apply updates from F5.

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