cbcvebase.
CVE-2026-66842
published 2026-09-02

CVE-2026-66842: BIG-IP has a vulnerability where an authenticated user of any role may be able to create administrative user accounts through an undisclosed request to Traffic…

PriorityP262high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
0.28%
20.3th percentile
BIG-IP has a vulnerability where an authenticated user of any role may be able to create administrative user accounts through an undisclosed request to Traffic Management User Interface (TMUI). Impact: This vulnerability may allow an authenticated attacker with network access to the BIG-IP management interface to escalate privileges by creating administrative accounts on the BIG-IP system. There is no data plane exposure; this is a control plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected

6 ranges
VendorProductVersion rangeFixed in
f5big-ip
f5big-ip>= 17.1.0 < 17.1.3.417.1.3.4
f5big-ip>= 17.5.0 < 17.5.1.817.5.1.8
f5big-ip>= 21.0.0 < 21.0.0.321.0.0.3
f5big-ip>= 21.1.0 < 21.1.0.121.1.0.1
f5big-iq>= 8.4.0 < 8.4.2.18.4.2.1

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv4.08.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/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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