CVE-2026-77816Network attack vectorHinoki check available

Information disclosure via administrative-client certificate validation

Published Oct 13, 2026 · Updated Oct 13, 2026

Certificate validation in IBM WebSphere Application Server Liberty lets man-in-the-middle attackers read administrative-client data. IBM identifies improper certificate validation but does not disclose the failed check, affected method, or certificate acceptance conditions. Affected versions are 17.0.0.3 through 26.0.0.9; exploitation requires interception of administrative-client traffic, not merely access to a listening server.

CVSS severity6.5
Medium
EPSS probability0.23%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
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Summary

What happened

Certificate validation in IBM WebSphere Application Server Liberty lets man-in-the-middle attackers read administrative-client data. IBM identifies improper certificate validation but does not disclose the failed check, affected method, or certificate acceptance conditions. Affected versions are 17.0.0.3 through 26.0.0.9; exploitation requires interception of administrative-client traffic, not merely access to a listening server.

The record

CVE
CVE-2026-77816
Published
Oct 13, 2026
Updated
Oct 13, 2026
Vendor
IBM
Product
IBM WebSphere Application Server Liberty
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 13, 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=17.0.0.3 <=26.0.0.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

IBM · IBM WebSphere Application Server Libertyversion=17.0.0.3 <=26.0.0.9

Published CVSS scores

6.5IBMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

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Technologies

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