CVE-2026-13163 (GCVE-0-2026-13163)

Vulnerability from cvelistv5 – Published: 2026-06-24 12:49 – Updated: 2026-06-24 13:07
VLAI
Title
Lack of input validation in Mailerup input parameter leads to Open Redirect
Summary
Open redirect vulnerability (CWE-601) in the _safe_redirect function of the click-tracking endpoint (/c/<token>/) in Mailerup <1.0.0 on all platforms allows remote unauthenticated attackers to redirect victims to arbitrary external sites and conduct phishing attacks via a crafted u query parameter, because the URL scheme is validated (blocking javascript: and data:) but the destination host is not restricted to an allowlist, and a signing.BadSignature exception is silently caught so a valid signed token is not required.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-24 13:06 UTC
CWE
  • CWE-601 - URL redirection to untrusted site ('open redirect')
Assigner
Secur0 CNA under the INCIBE root
CNA scorecard A 99/100 over 41 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Mailerup Mailerup Affected: 0 , < 1.0.1 (custom)
    cpe:2.3:a:mailerup:mailerup:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-24 12:40
Credits
Dario Rivas Quero from Secur0 security team Cristian Fernandez Cornejo from Secur0 security team Mario Alvarez Fernandez Xoan M. Otero Jorge Secur0 CNA
Show details on NVD website
To clipboard 

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