CVE-2024-28820Network attack vector

Authenticated memory corruption via unchecked delimiter count

Published Jun 27, 2024 · Updated Nov 4, 2024

Buffer overflow in OpenVPN Auth-LDAP 2.0.4 allows remote authenticated users to corrupt memory via a crafted challenge/response password. The extract_openvpn_cr function in src/openvpn-cr.c writes delimiter positions past the fixed tokenIndexes array before validating the field count. A valid LDAP username and control of the password field are required; published sources establish memory corruption but no reliable code-execution outcome.

CVSS severity6.3
Medium
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in OpenVPN Auth-LDAP 2.0.4 allows remote authenticated users to corrupt memory via a crafted challenge/response password. The extract_openvpn_cr function in src/openvpn-cr.c writes delimiter positions past the fixed tokenIndexes array before validating the field count. A valid LDAP username and control of the password field are required; published sources establish memory corruption but no reliable code-execution outcome.

The record

CVE
CVE-2024-28820
Published
Jun 27, 2024
Updated
Nov 4, 2024
Vendor
Three Rings
Product
OpenVPN Auth-LDAP
Classifications
CWE-125
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 27, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 4, 2024Record 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=2.04

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Three Rings · OpenVPN Auth-LDAPversion=2.04

Published CVSS scores

6.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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