CVE-2026-93991Public exploitNetwork attack vectorHinoki check available

Cross-namespace disclosure via negated namespace selector

Published Sep 19, 2026 · Updated Sep 19, 2026

Authorization bypass in Argo Workflows 4.1.0 through 4.1.3 allows remote authenticated users to read archived workflows across namespaces. In ListArchivedWorkflows, a NotEquals selector leaves the attacker-supplied namespace in the access review while the SQL query excludes that namespace. Namespace-scoped list permission is sufficient, and the response exposes other tenants' arguments, parameter values, annotations, and error details without write access.

CVSS severity8.3
High
EPSS probability0.44%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authorization bypass in Argo Workflows 4.1.0 through 4.1.3 allows remote authenticated users to read archived workflows across namespaces. In ListArchivedWorkflows, a NotEquals selector leaves the attacker-supplied namespace in the access review while the SQL query excludes that namespace. Namespace-scoped list permission is sufficient, and the response exposes other tenants' arguments, parameter values, annotations, and error details without write access.

The record

CVE
CVE-2026-93991
Published
Sep 19, 2026
Updated
Sep 19, 2026
Vendor
Argo Project
Product
Argo Workflows
Classifications
CWE-639, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 19, 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=4.1.0 <4.1.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Argo Project · Argo Workflowsversion=4.1.0 <4.1.4

Published CVSS scores

8.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
7.7GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1213Data from Information Repositories

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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