SB2026051427 - Remote denial of service in BIG-IP Next SPK/CNF SSL implementation



SB2026051427 - Remote denial of service in BIG-IP Next SPK/CNF SSL implementation

Published: May 14, 2026

Security Bulletin ID SB2026051427
CSH Severity
Medium
Patch available
NO
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Incorrect Calculation of Buffer Size (CVE-ID: CVE-2026-40618)

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to incorrect calculation of buffer size in the SSL profile when processing undisclosed traffic. A remote attacker can send crafted traffic to cause a denial of service.

This issue affects the data plane only and has no control plane exposure. Exploitation is possible when an SSL profile is configured on a virtual server on BIG-IP Virtual Edition without Intel QuickAssist Technology or on BIG-IP hardware platforms with the crypto.hwacceleration database variable disabled.


Remediation

Cybersecurity Help is not aware of any official remediation provided by the vendor.