# CVE-2023-6393: Quarkus: potential invalid reuse of context when @cacheresult on a uni is used

> Attackers can access sensitive data from other users' requests due to improper context reuse in cached Uni objects within Quarkus.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/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:** 6 Dec 2023
- **Updated:** 29 Sep 2026
- **Also known as:** GHSA-xfv5-jqgp-vqhj

## What is CVE-2023-6393?

CVE-2023-6393 is a medium-severity vulnerability in Red Hat build of Quarkus, published on 6 Dec 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A flaw was found in the Quarkus Cache Runtime. When request processing utilizes a Uni cached using @CacheResult and the cached Uni reuses the initial "completion" context, the processing switches to the cached Uni instead of the request context. This is a problem if the cached Uni context contains sensitive information, and could allow a malicious user to benefit from a POST request returning the response that is meant for another user, gaining access to sensitive data.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2023-6393?

4 open source packages ship an affected version, including io.quarkus:quarkus-cache. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `io.quarkus:quarkus-cache` | Maven | From 3.2.0.CR1 | 3.2.9.Final |
| `io.quarkus:quarkus-cache` | Maven | From 3.2.0.CR1 | 3.2.9.Final |
| `io.quarkus:quarkus-cache` | Maven | From 3.3.0.CR1 | 3.5.2 |
| `io.quarkus:quarkus-cache` | Maven | From 3.3.0.CR1 | 3.5.2 |

Products: Redhat Build of Quarkus.

## How do I fix CVE-2023-6393?

Upgrade io.quarkus:quarkus-cache to a fixed version for your release line: 3.2.9.Final or 3.5.2.

## Is CVE-2023-6393 being exploited?

There is no known exploitation of CVE-2023-6393 in the wild and no public exploit code.

## Other vulnerabilities in Red Hat build of Quarkus

- [CVE-2022-4492](https://insights.sbomify.com/CVE-2022-4492/): Undertow client not checking server identity presented by server certificate in https connections (high 7.5)
- [CVE-2023-2974](https://insights.sbomify.com/CVE-2023-2974/): quarkus-core vulnerable to client driven TLS cipher downgrading (medium 6.5)
- [CVE-2023-1664](https://insights.sbomify.com/CVE-2023-1664/): Keycloak Untrusted Certificate Validation vulnerability (medium 6.5)
- [CVE-2021-3914](https://insights.sbomify.com/CVE-2021-3914/): SmallRye Health UI Cross-site Scripting vulnerability (medium 6.1)
- [CVE-2021-3536](https://insights.sbomify.com/CVE-2021-3536/): Cross-site Scripting in Wildfly (medium 4.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-6393 and fix it if it is affected.

What it is: CVE-2023-6393 is a medium-severity vulnerability in Red Hat build of Quarkus, published on 6 Dec 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-6393 in the wild and no public exploit code.

Affected packages and fixed versions:
- io.quarkus:quarkus-cache (Maven): affected from 3.2.0.CR1; fixed in 3.2.9.Final
- io.quarkus:quarkus-cache (Maven): affected from 3.2.0.CR1; fixed in 3.2.9.Final
- io.quarkus:quarkus-cache (Maven): affected from 3.3.0.CR1; fixed in 3.5.2
- io.quarkus:quarkus-cache (Maven): affected from 3.3.0.CR1; fixed in 3.5.2

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-2023-6393/ (Markdown: https://insights.sbomify.com/CVE-2023-6393/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-6393
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-6393
- OSV: https://osv.dev/vulnerability/CVE-2023-6393

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-6393/
Summaries are generated and may contain mistakes; the official description above is the record.