CVE-2026-66842
Description
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.
How to fix
- F5 BIG-IP21.1.0.1, 21.0.0.3, 17.5.1.8, 17.1.3.4 or later
- F5 BIG-IQ8.4.2.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| F5 BIG-IP | 21.1.0 ≤ v < 21.1.0.1, 21.0.0 ≤ v < 21.0.0.3, 17.5.0 ≤ v < 17.5.1.8, 17.1.0 ≤ v < 17.1.3.4 | 21.1.0.1, 21.0.0.3, 17.5.1.8, 17.1.3.4 |
| F5 BIG-IQ | 8.4.0 ≤ v < 8.4.2.1 | 8.4.2.1 |
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