CVE-2026-6388 | Argocd-image-updater: argocd image updater: cross-namespace privilege escalation via insufficient namespace validation

A flaw was found in ArgoCD Image Updater. This vulnerability allows an attacker, with permissions to create or modify an ImageUpdater resource in a multi-tenant environment, to bypass namespace boundaries. By exploiting insufficient validation, the attacker can trigger unauthorized image updates on applications managed by other tenants. This leads to cross-namespace privilege escalation, impacting application integrity through unauthorized application updates.

Published: 2026-04-15 Last update: 2026-04-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-6388 is rated Low Risk (39.1/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.03%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-6388

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-16 0.03%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-6388

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
3.1 5.3 [email protected]

Weakness enumeration for CVE-2026-6388

OS Trackers for CVE-2026-6388

vendor priority summary link
redhat high https://access.redhat.com/security/cve/CVE-2026-6388

Affected software / configurations for CVE-2026-6388

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-6388

cvelogic Threat Intelligence