CVE-2021-21084: Adobe Experience Manager stored cross-site scripting vulnerability in resource resolver factory could lead to arbitrary code execution

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-28 · updated 2026-06-17
Weakness: CWE-79

Description

AEM's Cloud Service offering, as well as versions 6.5.7.0 (and below), 6.4.8.3 (and below) and 6.3.3.8 (and below) are affected by a stored Cross-Site Scripting (XSS) vulnerability that could be abused by an attacker to inject malicious scripts into vulnerable form fields. Malicious JavaScript may be executed in a victim’s browser when they browse to the page containing the vulnerable field.

Affected products

Adobe Experience Manager: through 6.3.3.8; from 6.4.0.0 before 6.4.8.4; from 6.5.0.0 before 6.5.8.0 — fixed in 6.4.8.4, 6.5.8.0
Adobe Experience Manager Cloud Service: all versions

How to fix

Upgrade to a fixed version: Adobe Experience Manager 6.4.8.4, 6.5.8.0. Check the vendor advisory for mitigations.

References

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