F5 BIG-IP AFM and DDoS Hybrid Defender fix a high-severity vulnerability

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[TLP:CLEAR] F5 BIG-IP AFM and DDoS Hybrid Defender fix a high-severity vulnerability

F5 has released an emergency fix (Hotfix-BIGIP-17.5.1.4.0.17.20-ENG.iso) for a high-severity vulnerability in BIG-IP AFM and DDoS Hybrid Defender [1]. After authentication, the hotfix can be downloaded from the MyF5 Downloads page. More detailed information can be found at [2][3].

F5 BIG-IP AFM and DDoS Hybrid Defender - DoS (CVE-2026-2507)

CVSS 8.7 (High)

Allows an unauthenticated remote attacker to carry out a DoS attack on the Traffic Management Microkernel (TMM) [1].

The vulnerability is present in products:

BIG-IP AFM; ==17.5.1.4;
BIG-IP DDoS Hybrid Defender; ==17.5.1.4;

CVSS: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

More information:

CVE-2026-2507 at cve.org, NVD
CWE-476: NULL Pointer Dereference at cwe.mitre.org

The vulnerability was publicly disclosed 18. 2. 2026.

Links

By CESNET, z.s.p.o. Michaela Ručková on 20. 2. 2026.

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[TLP:CLEAR] F5 BIG-IP AFM and DDoS Hybrid Defender fix a high-severity vulnerability

F5 BIG-IP AFM and DDoS Hybrid Defender - DoS (CVE-2026-2507)

CVSS 8.7 (High)

Links