Vulnerability in Pebcak Go-Mail
CVE-2025-59937
go-mail is a comprehensive library for sending mails with Go. In versions 0.7.0 and below, due to incorrect handling of the mail.Address values when a sender- or recipient address is passed to the corresponding MAIL FROM or RCPT TO commands of the SMTP client, there is a possibility of wrong address routing or even ESMTP parameter smuggling. For successful exploitation, it is required that the user's code allows for arbitrary mail address input (i. e. through a web form or similar). If only static mail addresses are used (i. e. in a config file) and the mail addresses in use do not consist of quoted local parts, this should not affect users. This issue is fixed in version 0.7.1
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (43.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Pebcak Go-Mail
- Wneessen Go-Mail — versions < 0.7.1
Weakness classification (CWE)
References
- github.com/wneessen/go-mail/security/advisories/GHSA-wpwj-69cm-q9c5 (Vendor Advisory)
- github.com/wneessen/go-mail/issues/495 (Exploit, Issue Tracking)
- github.com/wneessen/go-mail/pull/496 (Patch, Issue Tracking)
- github.com/wneessen/go-mail/commit/42e92cfe027be04aff72921adb0f72f11d517479 (Patch)
Frequently asked questions
- What is CVE-2025-59937?
- CVE-2025-59937 is a critical-severity vulnerability in Pebcak Go-Mail, classified under Argument Injection. CVSS score: 9.1/10. Published 2025-09-29.
- How severe is CVE-2025-59937?
- Critical severity. CVSS v3 base score is 9.1 out of 10.