Description
Jenkins Email Extension Plugin 1933.v45cec755423f and earlier allows inlining images as `base64` in email content by setting the `data-inline` attribute, without restrictions on the image URLs that can be inlined, allowing attackers able to control the email content to specify `file:` URLs for images to read arbitrary files from the Jenkins controller filesystem.
Affected products
jenkins: email extension
References1
- www.jenkins.io/security/advisory/2026-05-27/#SECURITY-3705 Vendor Advisory
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 22 · as of 14 November 2026
- CWE
- CWE-73
Could this be exploited in your environment?
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