Is CVE-2026-42919 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-42919 being exploited in the wild.

How severe is CVE-2026-42919?

Medium severity, with a CVSS score of 6.7, published 13 May 2026.

Which products and versions are affected?

F5 BIG-IP All supported versions (EoTS versions not evaluated); F5 BIG-IP Advanced WAF 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0; F5 Big-Ip Access Policy Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0; F5 Big-Ip Advanced Firewall Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0; and 1 more.

Is there a fix for CVE-2026-42919?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-42919 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-42919?

Check whether you run F5 BIG-IP, F5 BIG-IP Advanced WAF, F5 Big-Ip Access Policy Manager or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-42919: F5 BIG-IP privilege escalation in multiple modules

CVE-2026-42919 · Severity: medium · CVSS 6.7 · Published 2026-05-13

A vulnerability in F5 BIG-IP systems could allow an already authenticated administrator to gain higher levels of access than intended. BIG-IP is a suite of networking products used to manage and secure enterprise application traffic. If exploited, an attacker could bypass security boundaries to perform unauthorized actions or disrupt services, potentially compromising the integrity of the network infrastructure.

Technologies: F5 BIG-IP, F5 BIG-IP Advanced WAF, F5 Big-Ip Access Policy Manager, F5 Big-Ip Advanced Firewall Manager, F5 Big-Ip Local Traffic Manager. Vendors: F5.

Quick answers

Is CVE-2026-42919 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-42919 being exploited in the wild.
How severe is CVE-2026-42919?: Medium severity, with a CVSS score of 6.7, published 13 May 2026.
Which products and versions are affected?: F5 BIG-IP All supported versions (EoTS versions not evaluated); F5 BIG-IP Advanced WAF 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0; F5 Big-Ip Access Policy Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0; F5 Big-Ip Advanced Firewall Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0; and 1 more.
Is there a fix for CVE-2026-42919?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-42919 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-42919?: Check whether you run F5 BIG-IP, F5 BIG-IP Advanced WAF, F5 Big-Ip Access Policy Manager or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A stack-based buffer overflow (CWE-121) exists in multiple F5 BIG-IP modules, including APM, AFM, and Local Traffic Manager. The vulnerability is reachable over the network but requires high privileges (administrative access) as a precondition. An authenticated attacker can exploit this flaw to escalate their privileges and cross established security boundaries within the system. F5 has identified affected versions across the 16.x, 17.x, and 21.x branches; users are advised to consult the vendor advisory for specific patch versions.

Affected products

F5 BIG-IP Access Policy Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0
F5 BIG-IP Advanced Firewall Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0
F5 BIG-IP Advanced WAF 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0
F5 BIG-IP Local Traffic Manager 16.1.0 - 16.1.6, 17.5.0 - 17.5.1, 21.0.0

Timeline

2026-05-13: advisory: Initial publication of the vulnerability advisory

References

https://my.f5.com/manage/s/article/K000158971

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