Cisco Identity Services Engine Guest Portal Endpoint Posture Status Reporting improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.44

Summaryinfo

A vulnerability was found in Cisco Identity Services Engine and ISE Passive Identity Connector. It has been declared as problematic. This affects an unknown function of the component Guest Portal Endpoint Posture Status Reporting. Executing a manipulation can lead to improper authentication. This vulnerability is handled as CVE-2026-76439. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Cisco Identity Services Engine and ISE Passive Identity Connector (version now known). This vulnerability affects some unknown processing of the component Guest Portal Endpoint Posture Status Reporting. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect integrity. CVE summarizes:

A vulnerability in the endpoint posture status reporting functionality of the guest portal web application of Cisco ISE could allow an unauthenticated, remote attacker to submit forged posture status events into the endpoint posture pipeline. This vulnerability is due to insufficient authentication on an internal interface that is exposed through the guest portal. An attacker could exploit this vulnerability by sending a crafted request to an affected system. A successful exploit could allow the attacker to manipulate the posture status on the affected system.

The advisory is shared for download at sec.cloudapps.cisco.com. This vulnerability was named CVE-2026-76439 since 08/19/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/16/2026).

Upgrading eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (cisco): 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
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: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/19/2026 CVE reserved
09/16/2026 +28 days Advisory disclosed
09/16/2026 +0 days VulDB entry created
09/16/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: cisco.com

Advisory: sec.cloudapps.cisco.com
Status: Confirmed

CVE: CVE-2026-76439 (🔒)
GCVE (CVE): GCVE-0-2026-76439
GCVE (VulDB): GCVE-100-406216

Entryinfo

Created: 09/16/2026 23:41
Changes: 09/16/2026 23:41 (64)
Complete: 🔍
Cache ID: 216::103

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