Skip to main content

HPE Instant On EUVDEUVD-2026-89350

| CVE-2026-76731 MEDIUM
Improper Privilege Management (CWE-269)
2026-09-29 hpe GHSA-6g54-w9r4-mw9h
6.5
CVSS 3.1 · Vendor: hpe
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Reach captive portal over network
  2. Exploit
    Send crafted request bypassing auth check
  3. Execution
    Circumvent authentication controls
  4. Impact
    Read limited data and make limited changes

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V8 - Authorization Least privilege enforcement
MITRE ATT&CK

1 technique across 1 tactic: Privilege Escalation

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Exploitation Conditions

Exploitation requires that the target run HPE Networking Instant On (version ≤3.4.1.0) with the captive portal feature in use and network-reachable by the attacker - captive portals are typically exposed to guest/pre-authentication network clients, so this is often the default posture for deployments using the feature. No authentication, no user interaction, and no special client privileges are needed (PR:N/UI:N). Limiting factors: impact is inherently bounded (C:L/I:L, no availability impact), the vulnerability is confined to the captive-portal component rather than the full device, and sites that do not enable captive-portal functionality are not exposed.

Impact

The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N, base 6.5 Medium) describes a genuinely low-friction attack surface: network-reachable, low complexity, no privileges, no user interaction. Those access metrics alone would normally warrant urgency, but the impact metrics deliberately cap the severity - C:L/I:L/A:N means the bypass yields only 'limited access to some data' and 'limited changes,' not full compromise, consistent with the vendor description. There is no EPSS score, no CISA KEV listing, and no public POC in the provided data, so there is no evidence of active or imminent exploitation - the risk is currently theoretical/opportunistic rather than confirmed. No signals conflict: the network vector matches a captive-portal component that is by design internet/LAN-facing. Net assessment: a real but bounded issue - patch-worthy for exposed Instant On deployments, but not a drop-everything emergency given the limited technical impact and absence of exploitation evidence.

Exploit ScenarioDerived

An unauthenticated attacker on a network segment reachable by an HPE Networking Instant On captive portal sends crafted requests that circumvent the portal's authentication logic, bypassing the login gate. Once past it, the attacker reads a limited subset of portal/session data and makes limited configuration or state changes within the affected component. No public exploit code is identified at time of analysis, and no user interaction is required.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
No patch listed yet 0.3% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Sep 29, 2026

Authentication bypass in the captive portal of HPE Networking Instant On (all versions up to and including 3.4.1.0) lets a network-reachable, unauthenticated remote attacker circumvent the portal's authentication controls and obtain limited read access to data plus the ability to make limited changes inside that component. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N, base 6.5 Medium) confirms a low-friction attack path requiring no credentials and no user interaction, although the impact is bounded to the captive-portal component with no availability effect. No public exploit code or confirmed in-the-wild exploitation has been identified - no public exploit identified at time of analysis - and no EPSS score was supplied with the source data.

RemediationAI

The primary fix is to update HPE Networking Instant On to the fixed release identified in HPE security advisory hpesbnw05150en_us (https://support.hpe.com/hpesc/public/docDisplay?docId=hpesbnw05150en_us&docLocale=en_US); the exact patched version number is not supplied in this dataset, so the fixed version should be confirmed against that advisory, and any release that supersedes 3.4.1.0 is the target baseline for the affected range. If immediate upgrade is not possible, the most effective compensating control is to disable the captive portal feature entirely on affected controllers - this removes the exposed attack surface completely, with the clear trade-off that guest and pre-authentication onboarding workflows will stop functioning and guests will need an alternative onboarding method (for example pre-shared keys or a temporary open SSID with MAC-limited access). Where the portal must remain in service, restrict reachability so that the portal is exposed only to the intended guest VLAN/SSID and not to management, corporate, or internet-routed segments, recognising that this reduces but does not eliminate risk because the portal is by design reachable by unauthenticated clients. Additional hardening includes segmenting guest traffic from management interfaces, monitoring portal endpoints for anomalous or unexpected session/token behaviour, and treating the portal host as a low-trust asset until patched.

Affected VersionsENISA

Instant On 0.0.0.0 ≤3.4.1.0

Affected Packages

euvd instant_on no fix

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The vulnerable technology is the captive portal that HPE Networking Instant On exposes to pre-authentication clients - typically guests or unmanaged devices that have not yet been granted network access. Because a captive portal inherently sits in front of authentication, its HTTP/HTTPS session handling, redirect logic, and portal-access token validation run without an authenticated session, which is exactly why the assessed vector is PR:N/UI:N and AV:N. The supplied CPE, cpe:2.3:a:hewlett_packard_enterprise_(hpe):instant_on:*:*:*:*:*:*:*:*, identifies the affected product family with a wildcard version, while the EUVD record narrows the affected range to Instant On 0.0.0.0 through 3.4.1.0 ("Instant On 0.0.0.0 ≤3.4.1.0"). No CWE identifier was provided in the source data; the described behavior - bypassing existing authentication controls to obtain limited data access and limited write capability - is consistent with the improper-authentication / missing-authentication-for-critical-function class (CWE-287/CWE-306), but that mapping is an inference from the described behaviour and is not vendor-confirmed. The flaw is confined to the captive-portal component rather than the underlying device management plane, which is why confidentiality and integrity impacts are scored Low and availability is None (C:L/I:L/A:N).

Know when Instant On gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (hpe) PRIMARY 6.5 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
vuln.today AI 6.5 MEDIUM

Network-reachable captive portal, no auth or interaction (AV:N/AC:L/PR:N/UI:N); bypass grants only limited data read and limited changes within one component (C:L/I:L, S:U, A:N).

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (hpe).

CVSS VectorVendor: hpe

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None

DescriptionCVE.org

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.

Threat Intelligence Overview

EPSS Score
0.3%
Top 78% exploitable
Prevalence
Medium
SMB cloud-managed Wi-Fi/switch line, common in small business, not enterprise-ubiquitous
Data Quality
4 sources
Confidence: Medium

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 0.3%
Patch available No
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation
None
System Exposure· derived
Open
Automatable
Yes
Human Impact· derived
Medium
Technical Impact
Partial

Priority Score

32
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +32
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Privilege escalation occurs when an attacker leverages flaws in access control mechanisms to gain permissions beyond what they were originally granted.

CVE-2026-76722 CRITICAL
9.8 Sep 29

Unauthenticated remote command execution is possible on HPE Networking Instant On access points running firmware version

CVE-2026-76721 CRITICAL
9.8 Sep 29

Unauthenticated remote code execution in HPE Networking Instant On firmware through 3.4.1.0 allows an attacker who can r

CVE-2026-76725 CRITICAL
9.6 Sep 29

Authentication controls in the management protocol of HPE Networking Instant On access points (firmware ≤3.4.1.0) can be

CVE-2026-76724 CRITICAL
9.6 Sep 29

Unauthenticated command injection in the CLI of HPE Networking Instant On access points allows an attacker on the same a

CVE-2026-76723 CRITICAL
9.6 Sep 29

Unauthenticated attackers on the same Layer-2/wireless broadcast domain as an HPE Networking Instant On access point can

CVE-2026-76726 HIGH
8.1 Sep 29

An authentication bypass in the API endpoint of HPE Networking Instant ON (affected versions 0.0.0.0 through 3.4.1.0) al

CVE-2026-76728 HIGH
7.2 Sep 29

Server-side request forgery (SSRF) in the management API endpoint of HPE Networking Instant ON access points lets an aut

CVE-2026-76727 HIGH
7.2 Sep 29

Command injection in HPE Networking Instant ON firmware versions up to and including 3.4.1.0 allows an authenticated rem

CVE-2026-76729 MEDIUM
6.6 Sep 29

Memory corruption reachable through an unvalidated format string in the management API of HPE Networking Instant On acce

CVE-2026-76730 MEDIUM
6.5 Sep 29

Authentication bypass in the PAPI control-plane protocol of HPE Networking Instant On access points running firmware 3.4

CVE-2026-76732 MEDIUM
6.4 Sep 29

Local privilege escalation in HPE Networking Instant On firmware 3.4.1.0 and earlier allows an attacker who already hold

CVE-2026-76733 MEDIUM
4.9 Sep 29

Denial of service in HPE Networking Instant On firmware version 3.4.1.0 and earlier lets a remote attacker who already h

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy