CVE-2026-26964Public exploitNetwork attack vector

Slack OAuth secret disclosure via missing redaction

Published Feb 19, 2026 · Updated Feb 20, 2026

Information disclosure in Windmill 1.634.6 and earlier allows remote authenticated users to obtain a workspace Slack OAuth client secret. The get_settings handler returns slack_oauth_client_secret in plaintext because its non-admin response redaction omits that legacy field. Exploitation requires membership in the affected workspace and configured Slack OAuth; the secret permits Slack application impersonation or phishing flows, but not arbitrary Slack message access.

CVSS severity2.7
Low
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Windmill 1.634.6 and earlier allows remote authenticated users to obtain a workspace Slack OAuth client secret. The get_settings handler returns slack_oauth_client_secret in plaintext because its non-admin response redaction omits that legacy field. Exploitation requires membership in the affected workspace and configured Slack OAuth; the secret permits Slack application impersonation or phishing flows, but not arbitrary Slack message access.

The record

CVE
CVE-2026-26964
Published
Feb 19, 2026
Updated
Feb 20, 2026
Vendor
Windmill Labs
Product
Windmill
Classifications
CWE-200, T1552
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 20, 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=< 1.635.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Windmill Labs · Windmillversion=< 1.635.0

Published CVSS scores

2.7GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/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.

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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)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1552Unsecured Credentials

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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