What is CVE-2026-25529?

CVE-2026-25529 is a high-severity vulnerability in Postalserver Postal, classified under Cross-site Scripting. CVSS score: 8.1/10. Published 2026-03-12.

How severe is CVE-2026-25529?

High severity. CVSS v3 base score is 8.1 out of 10.

XSS in Postalserver Postal

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 "se…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.001 (16.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

Affected products

Postalserver Postal — versions < 3.3.5

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

https://github.com/postalserver/postal/security/advisories/GHSA-5f4r-5jpr-rfhc (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-25529?: CVE-2026-25529 is a high-severity vulnerability in Postalserver Postal, classified under Cross-site Scripting. CVSS score: 8.1/10. Published 2026-03-12.
How severe is CVE-2026-25529?: High severity. CVSS v3 base score is 8.1 out of 10.