Authentication Bypass in the Captive Portal of HPE Networking Instant On

published 2026-09-29 last mo. modified 2026-09-30 last mo. also EUVD-2026-89350

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

An authentication bypass vulnerability in the captive portal of HPE Networking Instant On could allow an unauthenticated remote attacker to circumvent existing authentication controls. Successful exploitation could allow an attacker to gain limited access to some data and to make limited changes within the affected component.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: last mo. (2026-09-30)

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Affected products

Hewlett Packard Enterprise (HPE) Instant ON

Classification

Weakness

CWE-269 Improper Privilege Management

References

support.hpe.com /hpesc/public/docDisplay?docId=hpesbnw05150en_us&docLocale=en_US

Sources

CVE List CVE-2026-76731
NVD CVE-2026-76731

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