# CVE-2023-32690: Responder can Invoke Undefined Behavior in libspdm Requester

> An attacker can cause undefined behavior and potential denial of service in libspdm Requesters by providing an unvalidated CTExponent value.

- **Severity:** Medium 5.7 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 1 Jun 2023
- **Updated:** 8 Jan 2025
- **Also known as:** GHSA-56h8-4gv5-jf2c

## What is CVE-2023-32690?

CVE-2023-32690 is a medium-severity vulnerability in DMTF libspdm, published on 1 Jun 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

libspdm is a sample implementation that follows the DMTF SPDM specifications. Prior to versions 2.3.3 and 3.0, following a successful CAPABILITIES response, a libspdm Requester stores the Responder's CTExponent into its context without validation. If the Requester sends a request message that requires a cryptography operation by the Responder, such as CHALLENGE, libspdm will calculate the timeout value using the Responder's unvalidated CTExponent.

A patch is available in version 2.3.3. A workaround is also available. After completion of VCA, the Requester can check the value of the Responder's CTExponent. If it greater than or equal to 64, then the Requester can stop communication with the Responder.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2023-32690?

It affects 1 product.


Products: Dmtf Libspdm.

## How do I fix CVE-2023-32690?

No fix has been published for CVE-2023-32690 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-32690 being exploited?

There is no known exploitation of CVE-2023-32690 in the wild and no public exploit code.

## Other vulnerabilities in DMTF libspdm

- [CVE-2023-31127](https://insights.sbomify.com/CVE-2023-31127/): DMTF-2023-0001: SPDM mutual authentication bypass (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-32690 and fix it if it is affected.

What it is: CVE-2023-32690 is a medium-severity vulnerability in DMTF libspdm, published on 1 Jun 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2023-32690 in the wild and no public exploit code.

Affected product: DMTF libspdm. 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-2023-32690/ (Markdown: https://insights.sbomify.com/CVE-2023-32690/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-32690
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-32690
- OSV: https://osv.dev/vulnerability/CVE-2023-32690

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-32690/
Summaries are generated and may contain mistakes; the official description above is the record.