Cyber Resilience

CVE-2026-42937

F5 Big-Ip Access Policy Manager 16.1.0 – 16.1.6

Published
13 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v4 7.1
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0020 10th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-42937 is a high-severity Incorrect Permission Assignment for Critical Resource (CWE-732) vulnerability in F5 Big-Ip Access Policy Manager. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique System Network Configuration Discovery (T1016); ranked at the 10th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Incorrect permission assignment vulnerabilities exist in BIG-IP and BIG-IQ TMOS Shell (tmsh) arp and ndp commands, and in BIG-IP iControl REST. These vulnerabilities may allow an authenticated attacker to view adjacent network information. Note: Software versions which have reached End…

more

of Technical Support (EoTS) are not evaluated.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1016 System Network Configuration Discovery Discovery
Adversaries may look for details about the network configuration and settings, such as IP and/or MAC addresses, of systems they access or through information discovery of remote systems.
Why these techniques?

Incorrect permissions on tmsh arp/ndp and iControl REST directly enable an authenticated attacker to perform System Network Configuration Discovery of adjacent hosts.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-42058Same product: F5 Big-Ip Access Policy Manager
CVE-2026-41217Same product: F5 Big-Ip Access Policy Manager
CVE-2026-40462Same product: F5 Big-Ip Access Policy Manager
CVE-2026-41959Same product: F5 Big-Ip Access Policy Manager
CVE-2023-22326Same product: F5 Big-Ip Access Policy Manager
CVE-2024-27202Same product: F5 Big-Ip Access Policy Manager
CVE-2026-39459Same product: F5 Big-Ip Access Policy Manager
CVE-2025-53856Same product: F5 Big-Ip Access Policy Manager
CVE-2026-32673Same product: F5 Big-Ip Access Policy Manager
CVE-2026-41953Same product: F5 Big-Ip Access Policy Manager

Affected Assets

f5
big-ip access policy manager
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip advanced firewall manager
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip advanced web application firewall
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip analytics
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip application acceleration manager
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip application security manager
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip application visibility and reporting
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip automation toolchain
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip carrier-grade nat
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
f5
big-ip container ingress services
16.1.0 — 16.1.6 · 17.1.0 — 17.1.3.1 · 17.5.0 — 17.5.1.4
+11 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-6 Least Privilege
  • AC-4 Information Flow Enforcement
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 7 hardening rules · 4 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authorization checks on tmsh arp/ndp commands and iControl REST endpoints so that only permitted subjects can retrieve adjacent-network information.

prevent

Requires that authenticated users and service accounts receive only the minimal privileges needed, eliminating the excessive permissions that enable the CWE-732 exposure.

prevent

Enforces information-flow policies that can block unauthorized disclosure of link-layer neighbor data across system interfaces.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 full match
prevents

Directly requires defining, enforcing, and reviewing access permissions and least privilege on resources.

PR.PS-01 mostly match
prevents

Hardened baselines and configuration management explicitly include correct permission settings for critical resources.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

By requiring owners to determine and document the exact permissions needed for each asset, the control reduces the likelihood that default or overly permissive file and resource permissions will be left in place.

prevents

Documented provisioning and revocation procedures reduce the chance that critical resources retain overly permissive default or leftover permissions after personnel changes.

prevents

Documented authorization, expiry rules, and audit logging of privileged accounts make it harder for critical resources to retain overly permissive or stale permission assignments.

prevents

Requiring explicit configuration of access controls and permissions for files, applications and services counters the assignment of overly permissive default or incorrect file-system rights.

prevents

Enforcing differentiated permissions on the source-code repository and program listings stops the assignment of overly broad default or inherited permissions to critical resources.

prevents

By defining and enforcing secure permission settings in configuration templates, the control reduces the likelihood that critical resources receive incorrect permission assignments.

References