F5 BIG-IP/BIG-IQ TMUI privileges management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.4$5k-$25k6.28-

Summaryinfo

A vulnerability was found in F5 BIG-IP and BIG-IQ. It has been rated as very critical. The affected element is an unknown function of the component TMUI. The manipulation leads to privileges management. This vulnerability is referenced as CVE-2026-66842. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in F5 BIG-IP and BIG-IQ (version unknown). It has been rated as very critical. This issue affects an unknown function of the component TMUI. The manipulation with an unknown input leads to a privileges management vulnerability. Using CWE to declare the problem leads to CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at my.f5.com. The identification of this vulnerability is CVE-2026-66842 since 07/29/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/02/2026). The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 9.4
VulDB Meta Temp Score: 9.4

VulDB Base Score: 9.9
VulDB Temp Score: 9.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/29/2026 CVE reserved
09/02/2026 +35 days Advisory disclosed
09/02/2026 +0 days VulDB entry created
09/02/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: f5.com

Advisory: my.f5.com
Status: Confirmed

CVE: CVE-2026-66842 (🔒)
GCVE (CVE): GCVE-0-2026-66842
GCVE (VulDB): GCVE-100-398195

Entryinfo

Created: 09/02/2026 18:02
Changes: 09/02/2026 18:02 (73)
Complete: 🔍
Cache ID: 216::103

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