# CVE-2020-36855: DCMTK dcmqrscp parseQuota stack-based overflow

> A stack-based buffer overflow in DCMTK's dcmqrscp allows local attackers to execute arbitrary code or cause denial of service.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Oct 2025
- **Updated:** 21 Oct 2025
- **Also known as:** DEBIAN-CVE-2020-36855, GHSA-7w2m-w84v-g952, UBUNTU-CVE-2020-36855

## What is CVE-2020-36855?

CVE-2020-36855 is a medium-severity memory corruption vulnerability in DCMTK, published on 21 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A security vulnerability has been detected in DCMTK up to 3.6.5. The affected element is the function parseQuota of the component dcmqrscp. The manipulation of the argument StorageQuota leads to stack-based buffer overflow. Local access is required to approach this attack. The exploit has been disclosed publicly and may be used. Upgrading to version 3.6.6 is sufficient to fix this issue. The identifier of the patch is 0fef9f02e. It is recommended to upgrade the affected component.

Weakness: CWE-121 (Stack-based Buffer Overflow), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2020-36855?

It affects 1 product.


Products: Offis Dcmtk.

## How do I fix CVE-2020-36855?

Upgrade to a fixed version.

## Is CVE-2020-36855 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-36855 exists.

## Other vulnerabilities in DCMTK

- [CVE-2024-47796](https://insights.sbomify.com/CVE-2024-47796/): Memory corruption in DCMTK (high 8.4)
- [CVE-2024-52333](https://insights.sbomify.com/CVE-2024-52333/): Memory corruption in DCMTK (high 8.4)
- [CVE-2024-27628](https://insights.sbomify.com/CVE-2024-27628/): Memory corruption in n/a (high 8.1)
- [CVE-2022-43272](https://insights.sbomify.com/CVE-2022-43272/): Denial of service in n/a (high 7.5)
- [CVE-2021-41687](https://insights.sbomify.com/CVE-2021-41687/): Denial of service in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-36855 and fix it if it is affected.

What it is: CVE-2020-36855 is a medium-severity memory corruption vulnerability in DCMTK, published on 21 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-36855 exists.

Affected product: DCMTK. 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-2020-36855/ (Markdown: https://insights.sbomify.com/CVE-2020-36855/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-36855
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-36855
- OSV: https://osv.dev/vulnerability/CVE-2020-36855

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-36855/
Summaries are generated and may contain mistakes; the official description above is the record.