CVE-2026-44037 Uncontrolled recursion in DCMTK JSON reader allows denial of service
Attackers can crash applications using DCMTK by sending deeply nested DICOM JSON, causing stack exhaustion and denial of service.
- 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
- None listed
What is CVE-2026-44037?
CVE-2026-44037 is a medium-severity denial of service vulnerability in OFFIS DCMTK, published on 8 Oct 2026. 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
Uncontrolled mutual recursion between DcmJSONReader::parseDataSet(), DcmJSONReader::parseElement() and DcmJSONReader::parseSequence() in dcmdata/libsrc/dcjsonrd.cc of OFFIS DCMTK 3.7.0 allows an attacker to cause a denial of service (stack exhaustion and process crash) via a crafted DICOM JSON document with deeply nested sequence (SQ) values. The json2dcm tool and any service that converts untrusted DICOM JSON (for example, DICOMweb payloads) with this reader are affected. The issue is fixed in commit cf955e64c35a1e07ba10698f639d5dcdec53b9d7.
Weakness: CWE-674
Which versions are affected by CVE-2026-44037?
How do I fix CVE-2026-44037?
No fix has been published for CVE-2026-44037 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-44037 being exploited?
There is no known exploitation of CVE-2026-44037 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-44037, GHSA-w8m4-mhcj-8r75, UBUNTU-CVE-2026-44037.