CVE-2026-48920 — Vulnerability in org.jenkins-ci.plugins:email-ext...

HIGH

Jenkins Email Extension Plugin: Attackers able to control email content may specify `file:` URLs for images to read arbitrary files from Jenkins controller filesystem

Published May 27, 2026Updated July 1, 2026Source: osv

Summary

Jenkins Email Extension Plugin 1933.v45cec755423f and earlier includes a feature that allows inlining images as `base64` in email content by setting the `data-inline` attribute. No restrictions are placed on the image URLs that can be inlined. This allows attackers able to control the email content to specify `file:` URLs for images to read arbitrary files from the Jenkins controller filesystem. The feature allowing inlining images as `base64` in email content by setting the `data-inline` attribute is removed from Email Extension Plugin 1933.1935.v276319e3cc47.

Advisory Timeline

First published May 27, 2026 (138 days ago).
Last revised July 1, 2026 — 35 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Maven

Update org.jenkins-ci.plugins:email-ext to 1933.1935.v276319e3cc47 or later

<!-- Update pom.xml dependency version to 1933.1935.v276319e3cc47 for org.jenkins-ci.plugins:email-ext -->

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: maven (1).

Package	Ecosystem	Affected	Fixed In
org.jenkins-ci.plugins:email-ext	maven	1806.v856a_01a_fa_39a_, 1814.v404722f34263, 1844.v3ea_a_b_842374a_, 1849.v6dd03b_f6e423 (+129 more)	1933.1935.v276319e3cc47

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-73
View on MITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 8.8 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References

Frequently Asked Questions

What is CVE-2026-48920?: Jenkins Email Extension Plugin: Attackers able to control email content may specify `file:` URLs for images to read arbitrary files from Jenkins controller filesystem This vulnerability has been assigned a severity rating of HIGH (CVSS score: 8.8/10).
How do I check if my project is affected by CVE-2026-48920?: CVE-2026-48920 affects org.jenkins-ci.plugins:email-ext. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2026-48920 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

8.8

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

GHSA-mq58-m26g-46gp

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