CVE-2026-40435

BIG-IP httpd access control vulnerability

MEDIUM
5.3
CVSS Score
Published: May 13, 2026 at 02:12 PM UTC
Updated: October 26, 2026 at 05:10 PM UTC
22 products affected across 1 vendorBig IP Access Policy ManagerBig IP Application Security ManagerBig IP Advanced Firewall Manager

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

When configured, IP-based access restrictions for httpd do not cover all endpoints, which may allow connections from blocked addresses.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1
16.1.0 ≤ v ≤ 16.1.617.1.0 ≤ v ≤ 17.1.317.5.0 ≤ v ≤ 17.5.1

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

Vendor AdvisoryPatchMitigation
Source: cverecord
https://my.f5.com/manage/s/article/K000156604

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMf5
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-420

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