CVE-2020-15077Network attack vector

Authenticated information disclosure via deferred-auth channel response

Published Jun 4, 2021 · Updated Aug 4, 2024

Authentication bypass in OpenVPN Access Server 2.8.7 and earlier allows remote authenticated users to access control-channel data via deferred authentication. The deferred-authentication handling returns channel data before access control completes, which can expose client-side scripts and other configuration information. Exploitation requires a valid locked or auto-login profile or credentials; the documented consequence is information disclosure and possible protected-network access, not arbitrary code execution.

CVSS severity5.3
Medium
EPSS probability1.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in OpenVPN Access Server 2.8.7 and earlier allows remote authenticated users to access control-channel data via deferred authentication. The deferred-authentication handling returns channel data before access control completes, which can expose client-side scripts and other configuration information. Exploitation requires a valid locked or auto-login profile or credentials; the documented consequence is information disclosure and possible protected-network access, not arbitrary code execution.

The record

CVE
CVE-2020-15077
Published
Jun 4, 2021
Updated
Aug 4, 2024
Vendor
OpenVPN Inc.
Product
OpenVPN Access Server
Classifications
CWE-287, CWE-305, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 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=2.8.7 and earlier versions

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OpenVPN Inc. · OpenVPN Access Serverversion=2.8.7 and earlier versions

Published CVSS scores

3.5NVDAV:N/AC:M/Au:S/C:P/I:N/A:N
5.3NVDCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-305Ineffective Access Control
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

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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