# CVE-2023-20866: Spring Session session ID can be logged to the standard output stream

> Attackers with log access can steal session IDs from standard output when using HeaderHttpSessionIdResolver, enabling session hijacking.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/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:** 13 Apr 2023
- **Updated:** 7 Feb 2025
- **Also known as:** GHSA-r7qr-f43m-pxfr

## What is CVE-2023-20866?

CVE-2023-20866 is a medium-severity vulnerability in Spring Session, published on 13 Apr 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

In Spring Session version 3.0.0, the session id can be logged to the standard output stream. This vulnerability exposes sensitive information to those who have access to the application logs and can be used for session hijacking. Specifically, an application is vulnerable if it is using HeaderHttpSessionIdResolver.

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

## Which versions are affected by CVE-2023-20866?

2 open source packages ship an affected version, including org.springframework.session:spring-session-core. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.springframework.session:spring-session-core` | Maven | From 3.0.0 | 3.0.1 |
| `org.springframework.session:spring-session-core` | Maven | From 3.0.0 | 3.0.1 |

Products: Vmware Spring Session.

## How do I fix CVE-2023-20866?

Upgrade org.springframework.session:spring-session-core to 3.0.1 or later.

## Is CVE-2023-20866 being exploited?

There is no known exploitation of CVE-2023-20866 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-20866 and fix it if it is affected.

What it is: CVE-2023-20866 is a medium-severity vulnerability in Spring Session, published on 13 Apr 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-2023-20866 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.springframework.session:spring-session-core (Maven): affected from 3.0.0; fixed in 3.0.1
- org.springframework.session:spring-session-core (Maven): affected from 3.0.0; fixed in 3.0.1

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-2023-20866/ (Markdown: https://insights.sbomify.com/CVE-2023-20866/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-20866
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-20866
- OSV: https://osv.dev/vulnerability/CVE-2023-20866

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-20866/
Summaries are generated and may contain mistakes; the official description above is the record.