CVE-2026-38819Public exploitHinoki check available

Gateway memory exhaustion via leaked client allocations

Published Aug 28, 2026 · Updated Aug 28, 2026

Memory leaks in openNDS before 11.0.0 allow remote attackers on the captive portal network to exhaust gateway memory through portal requests. The client_auth path overwrites pointers into a reused response buffer, while _client_free_node() fails to release every client allocation. Access to the captive portal network is required; repeated unauthenticated requests can consume all device memory within minutes and interrupt gateway service.

CVSS severity5.3
Medium
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Memory leaks in openNDS before 11.0.0 allow remote attackers on the captive portal network to exhaust gateway memory through portal requests. The client_auth path overwrites pointers into a reused response buffer, while _client_free_node() fails to release every client allocation. Access to the captive portal network is required; repeated unauthenticated requests can consume all device memory within minutes and interrupt gateway service.

The record

CVE
CVE-2026-38819
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
openNDS
Product
openNDS
Classifications
CWE-401, T1499
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <11.0.0

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

openNDS · openNDSversion=0 <11.0.0

Published CVSS scores

5.3NVDCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499Endpoint Denial of Service

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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