CVE-2026-25529

Postal is an open source SMTP server. Postal versions less than 3.3.5 had a HTML injection vulnerability that allowed unescaped data to be included in the admin interface. The primary way for unescaped data to be added is via the API's "send/raw" method. This could allow arbitrary HTML to be injected in to the page which may modify the page in a misleading way or allow for unauthorised javascript to be executed. Fixed in 3.3.5 and higher.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/postalserver/postal/security/advisories/GHSA-5f4r-5jpr-rfhc	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:postalserver:postal:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-12 17:16

Updated : 2026-06-17 10:24

NVD link : CVE-2026-25529

Mitre link : CVE-2026-25529

CVE.ORG link : CVE-2026-25529

JSON object : View

Products Affected

postalserver

postal

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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