CVE-2025-5256 | Open Redirect vulnerability on user unlock path

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.

Published: 2025-05-28 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-5256 is rated Low Risk (35.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.19%). 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-2025-5256

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 2026-03-24 0.05% 0.19% +0.14%
2 2026-03-14 0.03% 0.05% +0.02%
3 2025-11-21 — 0.03% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-5256

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N 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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.5 [email protected]

Weakness enumeration for CVE-2025-5256

GitHub Security Advisory for CVE-2025-5256

GHSA-6vx9-9r2g-8373 · Severity: medium · Ecosystem: composer — Mautic has an Open Redirect vulnerability on user unlock path.

Affected software / configurations for CVE-2025-5256

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-5256

cvelogic Threat Intelligence