Medium severity · published Feb 18, 2025
CVE-2025-0521
Post SMTP <= 3.0.2 - Unauthenticated Stored Cross-Site Scripting
6.1
CVSS
0.3%
EPSS
No
On KEV
Description
The Post SMTP plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the from and subject parameter in all versions up to, and including, 3.0.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected product
PS
Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
saadiqbal
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-0521
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-0521
Patch
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3237626%40post-smtp%2Ftrunk&old=3229076%40post-smtp%2Ftrunk&sfp_email=&sfph_mail=
Third Party Advisory
https://www.wordfence.com/threat-intel/vulnerabilities/id/366dfbf1-870c-4ce3-abc4-a2b2f4e72175?source=cve
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