How severe is CVE-2026-41227?

CVE-2026-41227 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-41227 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-41227?

CVE-2026-41227 primarily affects F5 Big-ip Advanced Web Application Firewall. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-41227?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-41227 have an EU (EUVD) identifier?

Yes. CVE-2026-41227 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29987.

When was CVE-2026-41227 published?

CVE-2026-41227 was published on 2026-05-13 and last updated on 2026-06-24.

CVE-2026-41227

CVE-2026-41227 is a high-severity vulnerability in F5 Big-ip Advanced Web Application Firewall with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.7
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29987
Weakness: CWE-770
Affected product: F5 Big-ip Advanced Web Application Firewall
Published: 2026-05-13
Last modified: 2026-06-24

Description

On an HTTP/2 virtual server with Layer 7 DoS Protection configured, undisclosed traffic can result in an increase in memory consumption causing the Traffic Management Microkernel (TMM) process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Frequently asked questions

What is CVE-2026-41227?: On an HTTP/2 virtual server with Layer 7 DoS Protection configured, undisclosed traffic can result in an increase in memory consumption causing the Traffic Management Microkernel (TMM) process to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
How severe is CVE-2026-41227?: CVE-2026-41227 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-41227 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-41227?: CVE-2026-41227 primarily affects F5 Big-ip Advanced Web Application Firewall. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-41227?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-41227 have an EU (EUVD) identifier?: Yes. CVE-2026-41227 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29987.
When was CVE-2026-41227 published?: CVE-2026-41227 was published on 2026-05-13 and last updated on 2026-06-24.

References

https://my.f5.com/manage/s/article/K000158979

Affected products (3)

cpe:2.3:a:f5:big-ip_advanced_web_application_firewall:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_ddos_hybrid_defender:*:*:*:*:*:*:*:*

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