CVE-2026-21295 is classified as an Open Redirect vulnerability (CWE-601) affecting multiple versions of Adobe Commerce, including 2.4.9-alpha3, 2.4.8-p3, 2.4.7-p8, 2.4.6-p13, 2.4.5-p15, 2.4.4-p16, and earlier. The vulnerability arises when the application improperly handles URL redirection parameters, allowing an attacker to craft a URL that redirects users to an untrusted, potentially malicious external site. This can be exploited by tricking users into clicking on specially crafted links, leading to phishing attacks, credential theft, or malware distribution. The vulnerability requires user interaction and has a high attack complexity, as the attacker must convince users to follow the malicious link. The CVSS v3.1 score is 3.1, reflecting no impact on confidentiality, low impact on integrity, no impact on availability, network attack vector, no privileges required, and user interaction needed. No public exploits have been reported yet, and no patches are currently linked, indicating that remediation may be pending or in progress. The vulnerability's root cause is insufficient validation or sanitization of redirect URLs within Adobe Commerce's web application logic.

The primary impact of this vulnerability is the facilitation of phishing and social engineering attacks. Attackers can exploit the open redirect to make malicious URLs appear legitimate by using trusted Adobe Commerce domains, increasing the likelihood that users will click on them. This can lead to credential compromise, malware infections, or other downstream attacks. While the vulnerability itself does not directly compromise system confidentiality, integrity, or availability, it serves as an enabler for more severe attacks. Organizations running affected Adobe Commerce versions risk reputational damage and potential customer trust erosion if users fall victim to redirected malicious sites. The requirement for user interaction and the high complexity of exploitation limit the scope of impact but do not eliminate the risk, especially in environments with high user traffic and e-commerce transactions.

1. Implement strict validation and sanitization of all URL redirection parameters to ensure they only point to trusted internal domains. 2. Employ allowlisting for redirect URLs rather than blacklisting to prevent bypasses. 3. Educate users and employees about the risks of clicking on suspicious links, especially those purporting to come from trusted e-commerce platforms. 4. Monitor web traffic and logs for unusual redirect patterns or spikes in redirected traffic to unknown domains. 5. Apply security headers such as Content Security Policy (CSP) to restrict navigation to trusted domains. 6. Stay updated with Adobe Commerce security advisories and apply patches promptly once released. 7. Use multi-factor authentication (MFA) to reduce the impact of credential theft resulting from phishing. 8. Consider implementing URL rewriting or intermediate warning pages for external redirects to alert users before leaving the trusted domain.