# 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

> Attackers controlling email content can read arbitrary files from the Jenkins controller filesystem by specifying file URLs in inline images.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 May 2026
- **Updated:** 27 May 2026
- **Also known as:** GHSA-mq58-m26g-46gp

## What is CVE-2026-48920?

CVE-2026-48920 is a high-severity path traversal vulnerability in Jenkins Email Extension Plugin, published on 27 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official 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.

Weakness: CWE-73 (External Control of File Name or Path)

## Which versions are affected by CVE-2026-48920?

2 open source packages ship an affected version, including org.jenkins-ci.plugins:email-ext. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.jenkins-ci.plugins:email-ext` | Maven | All versions | 1933.1935.v276319e3cc47 |
| `org.jenkins-ci.plugins:email-ext` | Maven | All versions | 1933.1935.v276319e3cc47 |

Products: Jenkins Email Extension.

## How do I fix CVE-2026-48920?

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

## Is CVE-2026-48920 being exploited?

There is no known exploitation of CVE-2026-48920 in the wild and no public exploit code.

## Other vulnerabilities in Jenkins Email Extension Plugin

- [CVE-2023-25765](https://insights.sbomify.com/CVE-2023-25765/): Sandbox escape in Jenkins Email Extension Plugin (critical 9.9)
- [CVE-2019-1003032](https://insights.sbomify.com/CVE-2019-1003032/): Script security sandbox bypass in Jenkins Email Extension Plugin (critical 9.9)
- [CVE-2020-2232](https://insights.sbomify.com/CVE-2020-2232/): Jenkins Email Extension Plugin SMTP password transmitted and displayed in plain text (high 7.5)
- [CVE-2018-1000176](https://insights.sbomify.com/CVE-2018-1000176/): Jenkins Email Extension Plugin showed plain text SMTP password in configuration form field (medium 6.5)
- [CVE-2023-25763](https://insights.sbomify.com/CVE-2023-25763/): Cross-site Scripting in Jenkins Email Extension Plugin (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48920 and fix it if it is affected.

What it is: CVE-2026-48920 is a high-severity path traversal vulnerability in Jenkins Email Extension Plugin, published on 27 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-48920 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.jenkins-ci.plugins:email-ext (Maven): affected all versions; fixed in 1933.1935.v276319e3cc47
- org.jenkins-ci.plugins:email-ext (Maven): affected all versions; fixed in 1933.1935.v276319e3cc47

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-48920/ (Markdown: https://insights.sbomify.com/CVE-2026-48920/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48920
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48920
- OSV: https://osv.dev/vulnerability/CVE-2026-48920

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-48920/
Summaries are generated and may contain mistakes; the official description above is the record.