# CVE-2026-12805: OFFIS DCMTK ofxml.cc parseFile heap-based overflow

> A heap-based buffer overflow in DCMTK's XML parser allows remote attackers to execute arbitrary code or cause denial of service via crafted files.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 21 Jun 2026
- **Updated:** 23 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-12805, GHSA-35pp-gpq2-4898, UBUNTU-CVE-2026-12805

## What is CVE-2026-12805?

CVE-2026-12805 is a medium-severity memory corruption vulnerability in OFFIS DCMTK, published on 21 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A flaw has been found in OFFIS DCMTK up to 3.7.0. The affected element is the function XMLNode::parseFile in the library ofstd/libsrc/ofxml.cc. Executing a manipulation can lead to heap-based buffer overflow. The attack may be performed from remote. The exploit has been published and may be used. This patch is called 1d4b3815c0987840a983160bfc671fef63a3105b. It is best practice to apply a patch to resolve this issue. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

Weakness: CWE-122 (Heap-based Buffer Overflow), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-12805?


## How do I fix CVE-2026-12805?

Apply the vendor's patch.

## Is CVE-2026-12805 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-12805 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-12805 and fix it if it is affected.

What it is: CVE-2026-12805 is a medium-severity memory corruption vulnerability in OFFIS DCMTK, published on 21 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-12805 exists.

Affected product: OFFIS 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-2026-12805/ (Markdown: https://insights.sbomify.com/CVE-2026-12805/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-12805
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-12805
- OSV: https://osv.dev/vulnerability/CVE-2026-12805

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-12805/
Summaries are generated and may contain mistakes; the official description above is the record.