What’s Vulnerable › Vulnerabilities

CVE-2021-42650

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-10-18 · updated 2026-06-17
• Weakness: CWE-79

Description

Cross Site Scripting (XSS vulnerability exists in Portainer before 2.9.1 via the node input box in Custom Templates.

Affected products

• portainer: before 2.9.1 — fixed in 2.9.1

How to fix

Upgrade to a fixed version: portainer 2.9.1. Check the vendor advisory for mitigations.

References

• https://github.com/portainer/portainer/pull/5766
• https://github.com/purple-WL/Security-vulnerability/blob/main/Portainer%20Custom%20Templates%20xss
• https://github.com/portainer/portainer/pull/5766
• https://github.com/purple-WL/Security-vulnerability/blob/main/Portainer%20Custom%20Templates%20xss

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