# CVE-2026-86321: java-json-tools jackson-coreutils URL Validation JsonLoader.java JsonLoader.fromURL server-side request forgery

> Attackers can exploit server-side request forgery in jackson-coreutils to access internal resources or bypass security controls.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Sep 2026
- **Updated:** 8 Sep 2026
- **Also known as:** GHSA-rrq3-h776-pmxg

## What is CVE-2026-86321?

CVE-2026-86321 is a medium-severity server-side request forgery vulnerability in java-json-tools jackson-coreutils, published on 7 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was found in java-json-tools jackson-coreutils 2.0. Affected by this issue is the function JsonLoader.fromURL of the file src/main/java/com/github/fge/jackson/JsonLoader.java of the component URL Validation. The manipulation results in server-side request forgery. It is possible to launch the attack remotely. The exploit has been made public and could be used. The project was informed of the problem early through an issue report but has not responded yet.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-86321?


## How do I fix CVE-2026-86321?

No fix has been published for CVE-2026-86321 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-86321 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86321 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-86321 and fix it if it is affected.

What it is: CVE-2026-86321 is a medium-severity server-side request forgery vulnerability in java-json-tools jackson-coreutils, published on 7 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86321 exists.

Affected product: java-json-tools jackson-coreutils. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-86321/ (Markdown: https://insights.sbomify.com/CVE-2026-86321/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-86321
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-86321
- OSV: https://osv.dev/vulnerability/CVE-2026-86321

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-86321/
Summaries are generated and may contain mistakes; the official description above is the record.