CVE-2025-5256: Open Redirect (CVSS 5.4)

Description

SummaryThis advisory addresses an Open Redirection vulnerability in Mautic's user unlocking endpoint. This vulnerability could be exploited by an attacker to redirect legitimate users to malicious websites, potentially leading to phishing attacks or the delivery of exploit kits. Open Redirection via returnUrl Parameter: An Open Redirection vulnerability exists in the /s/action/unlock/user.user/0 endpoint. The returnUrl parameter, intended for post-action redirection, is not properly validated. This allows an attacker to craft a URL that, when clicked by a user, redirects them to an arbitrary external website controlled by the attacker. MitigationUpdate Mautic to a version that properly validates or sanitizes the returnUrl parameter to ensure that redirects only occur to trusted, internal URLs or explicitly whitelisted domains.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Weakness Type (CWE)

CWE-601 CWE-601

References

Other References

https://github.com/mautic/mautic/security/advisories/GHSA-6vx9-9r2g-8373

Frequently Asked Questions

What is CVE-2025-5256? +

SummaryThis advisory addresses an Open Redirection vulnerability in Mautic's user unlocking endpoint. This vulnerability could be exploited by an attacker to redirect legitimate users to malicious websites, potentially leading to phishing attacks or the delivery of exploit kits. Open Redirection via returnUrl Parameter: An Open Redirection vulnerability exists in the /s/action/unlock/user.user/0 endpoint. The returnUrl parameter, intended for post-action redirection, is not properly validated. This allows an attacker to craft a URL that, when clicked by a user, redirects them to an arbitrary external website controlled by the attacker. MitigationUpdate Mautic to a version that properly validates or sanitizes the returnUrl parameter to ensure that redirects only occur to trusted, internal URLs or explicitly whitelisted domains. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2025-5256? +

CVE-2025-5256 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2025-5256? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2025-5256