# CVE-2026-9334: Memory corruption in Cpanel::JSON::XS

> Attackers can cause crashes or potential code execution in Perl applications using Cpanel::JSON::XS with duplicate key handling enabled.

- **Severity:** High 7.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 3 Jun 2026
- **Updated:** 3 Jun 2026
- **Also known as:** AZL-89396, DEBIAN-CVE-2026-9334, GHSA-qfqj-xxqv-cxfw, UBUNTU-CVE-2026-9334

## What is CVE-2026-9334?

CVE-2026-9334 is a high-severity memory corruption vulnerability in RURBAN Cpanel::JSON::XS, published on 3 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Cpanel::JSON::XS versions before 4.41 for Perl allow type confusion via duplicate object keys when dupkeys_as_arrayref is enabled.

decode_hv() collapses duplicate object keys into an array reference under dupkeys_as_arrayref. The branch reached for a duplicate key tests `SvTYPE (old_value) != SVt_RV && SvTYPE (SvRV (old_value)) != SVt_PVAV`, which evaluates SvRV(old_value) before establishing that old_value is a reference. When the existing value is a plain scalar rather than an array reference, a non-reference scalar is dereferenced as a reference.

A caller decoding untrusted JSON with dupkeys_as_arrayref enabled is crashed, and the incompatible access follows a pointer taken from attacker controlled scalar contents.

Weakness: CWE-843 (Access of Resource Using Incompatible Type)

## Which versions are affected by CVE-2026-9334?

It affects 1 product.


Products: Rurban Cpanel\.

## How do I fix CVE-2026-9334?

Upgrade to a fixed version.

## Is CVE-2026-9334 being exploited?

There is no known exploitation of CVE-2026-9334 in the wild and no public exploit code.

## Other vulnerabilities in RURBAN Cpanel::JSON::XS

- [CVE-2022-48623](https://insights.sbomify.com/CVE-2022-48623/): Information disclosure in n/a (critical 9.1)
- [CVE-2026-9516](https://insights.sbomify.com/CVE-2026-9516/): Denial of service in Cpanel::JSON::XS (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-9334 and fix it if it is affected.

What it is: CVE-2026-9334 is a high-severity memory corruption vulnerability in RURBAN Cpanel::JSON::XS, published on 3 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-9334 in the wild and no public exploit code.

Affected product: RURBAN Cpanel::JSON::XS. 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-2026-9334/ (Markdown: https://insights.sbomify.com/CVE-2026-9334/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-9334
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-9334
- OSV: https://osv.dev/vulnerability/CVE-2026-9334

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-9334/
Summaries are generated and may contain mistakes; the official description above is the record.