Critical severity · published Oct 21, 2026
CVE-2026-111832
WordPress WP Mailster plugin <= 1.9.1.0 - Arbitrary File Upload vulnerability
10.0
CVSS
0.4%
EPSS
No
On KEV
Description
Unrestricted Upload of File with Dangerous Type vulnerability in WP Mailster WP Mailster wp-mailster allows Upload a Web Shell to a Web Server.This issue affects WP Mailster: from n/a through 1.9.1.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WM
WP Mailster · WP Mailster
through 1.9.1.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-111832
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-111832
patchstack.com
https://patchstack.com/database/wordpress/plugin/wp-mailster/vulnerability/wordpress-wp-mailster-plugin-1-9-1-0-arbitrary-file-upload-vulnerability?_s_id=cve
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