CVE-2026-41218
published 2026-05-13CVE-2026-41218: When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the urlcatquery…
PriorityP346high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.26%
17.9th percentile
When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the urlcatquery command), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Affected
89 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| f5 | big-ip | >= 16.1.0 < * | * |
| f5 | big-ip | >= 17.1.0 < 17.1.3.1 | 17.1.3.1 |
| f5 | big-ip | >= 17.5.0 < 17.5.1.4 | 17.5.1.4 |
| f5 | big-ip | >= 21.0.0 < 21.0.0.1 | 21.0.0.1 |
| f5 | big-ip_access_policy_manager | — | — |
| f5 | big-ip_access_policy_manager | 16.1.0 – 16.1.6 | — |
| f5 | big-ip_access_policy_manager | 17.1.0 – 17.1.3 | — |
| f5 | big-ip_access_policy_manager | 17.5.0 – 17.5.1 | — |
| f5 | big-ip_advanced_firewall_manager | — | — |
| f5 | big-ip_advanced_firewall_manager | 16.1.0 – 16.1.6 | — |
| f5 | big-ip_advanced_firewall_manager | 17.1.0 – 17.1.3 | — |
| f5 | big-ip_advanced_firewall_manager | 17.5.0 – 17.5.1 | — |
| f5 | big-ip_advanced_web_application_firewall | — | — |
| f5 | big-ip_advanced_web_application_firewall | 16.1.0 – 16.1.6 | — |
| f5 | big-ip_advanced_web_application_firewall | 17.1.0 – 17.1.3 | — |
| f5 | big-ip_advanced_web_application_firewall | 17.5.0 – 17.5.1 | — |
| f5 | big-ip_analytics | — | — |
| f5 | big-ip_analytics | 16.1.0 – 16.1.6 | — |
| f5 | big-ip_analytics | 17.1.0 – 17.1.3 | — |
| f5 | big-ip_analytics | 17.5.0 – 17.5.1 | — |
| f5 | big-ip_application_acceleration_manager | — | — |
| f5 | big-ip_application_acceleration_manager | 16.1.0 – 16.1.6 | — |
| f5 | big-ip_application_acceleration_manager | 17.1.0 – 17.1.3 | — |
| f5 | big-ip_application_acceleration_manager | 17.5.0 – 17.5.1 | — |
| f5 | big-ip_application_security_manager | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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
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VulDB
F5 BIG-IP prior 17.1.3.1/17.5.1.4/21.0.0.1 Traffic Management Microkernel use after free (K000160875 / Nessus ID 316105)
vuldb·2026-05-24·CVSS 8.7
CVE-2026-41218 [HIGH] F5 BIG-IP prior 17.1.3.1/17.5.1.4/21.0.0.1 Traffic Management Microkernel use after free (K000160875 / Nessus ID 316105)
A vulnerability labeled as critical has been found in F5 BIG-IP. Affected by this issue is some unknown functionality of the component Traffic Management Microkernel. Executing a manipulation can lead to use after free.
This vulnerability is tracked as CVE-2026-41218. The attack can be launched remotely. No exploit exists.
The affected component should be upgraded.
GHSA
GHSA-65gg-93p6-xmj9: When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the url
ghsa_unreviewed·2026-05-13
CVE-2026-41218 [HIGH] CWE-416 GHSA-65gg-93p6-xmj9: When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the url
When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the urlcatquery command), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
F5
CVE-2026-41218: When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLAS...
vendor_f5·2026-05-13·CVSS 8.7
CVE-2026-41218 [HIGH] CWE-416 CVE-2026-41218: When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLAS...
CVE-2026-41218: When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLAS...
When BIG-IP PEM iRules are configured on a virtual server (iRules using commands starting with CLASSIFICATION::, CLASSIFY::, PEM::, PSC::, and the urlcatquery command), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Affected Products: BIG-IP PEM
F5 Advisory Articles: K000160875
F5 References: https://my.f5.com/manage/s/article/K000160875
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-05-13
Published