# CVE-2026-84655: Other in Jenkins

> Attackers can inject arbitrary fields into JSON and Python API responses by controlling map property names due to improper escaping in Jenkins.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N`)
- **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:** 2 Sep 2026
- **Updated:** 2 Sep 2026
- **Also known as:** BIT-jenkins-2026-84655, GHSA-g8v4-mgp3-5f84, MINI-477x-3q5j-fc42, MINI-8gch-mr9w-xmxm, MINI-g92v-9qgp-95rx, MINI-mx7r-jfw3-r6mq, MINI-qq8j-vvhr-3677, MINI-x49j-qcfp-x5x7, MINI-x8vh-xj2r-f8wx

## What is CVE-2026-84655?

CVE-2026-84655 is a medium-severity vulnerability in Jenkins Jenkins, published on 2 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Jenkins 2.579 and earlier, LTS 2.568.2 and earlier does not escape map keys when serializing objects as JSON and Python through its REST API, allowing attackers able to control map property names to inject arbitrary fields into JSON and Python API responses.

Weakness: CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2026-84655?

1 open source package ship an affected version, including jenkins. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `jenkins` | Bitnami | All versions | 2.568.3, 2.580.0 |

Products: Jenkins Jenkins.

## How do I fix CVE-2026-84655?

Upgrade jenkins to a fixed version for your release line: 2.568.3 or 2.580.0.

## Is CVE-2026-84655 being exploited?

There is no known exploitation of CVE-2026-84655 in the wild and no public exploit code.

## Other vulnerabilities in Jenkins Jenkins

- [CVE-2024-23897](https://insights.sbomify.com/CVE-2024-23897/): Jenkins Command Line Interface (CLI) Path Traversal (critical 9.8, exploited in the wild)
- [CVE-2018-1000861](https://insights.sbomify.com/CVE-2018-1000861/): Jenkins Stapler Web Framework Deserialization of Untrusted Data (critical 9.8, exploited in the wild)
- [CVE-2017-1000353](https://insights.sbomify.com/CVE-2017-1000353/): Jenkins Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2015-5317](https://insights.sbomify.com/CVE-2015-5317/): Jenkins User Interface (UI) Information Disclosure (high 7.5, exploited in the wild)
- [CVE-2021-21690](https://insights.sbomify.com/CVE-2021-21690/): Multiple vulnerabilities allow bypassing path filtering of agent-to-controller access control in Jenkins (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-84655 and fix it if it is affected.

What it is: CVE-2026-84655 is a medium-severity vulnerability in Jenkins Jenkins, published on 2 Sep 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-2026-84655 in the wild and no public exploit code.

Affected packages and fixed versions:
- jenkins (Bitnami): affected all versions; fixed in 2.568.3, 2.580.0

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-2026-84655/ (Markdown: https://insights.sbomify.com/CVE-2026-84655/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-84655
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-84655
- OSV: https://osv.dev/vulnerability/CVE-2026-84655

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-84655/
Summaries are generated and may contain mistakes; the official description above is the record.