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TI-2021-18378 Aliases CVE-2021-41690GHSA-xqr6-h56f-8r2j

DCMTK through 3.6.6 does not handle memory free properly.

Priority MEDIUM 43CWE-401Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-401.

Summary

DCMTK through 3.6.6 does not handle memory free properly. The malloced memory for storing all file information are recorded in a global variable LST and are not freed properly. Sending specific requests to the dcmqrdb program can incur a memory leak. An attacker can use it to launch a DoS attack.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01838 79th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:offis:dcmtk:*:*:*:*:*:*:*:*up to 3.6.6VulnerableOFFIS
  • cpe:2.3:a:offis:dcmtk:*:*:*:*:*:*:*:* Versions up to 3.6.6 Vulnerable ·OFFIS

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-41690
  2. 2026-10-03 Alias added: GHSA-xqr6-h56f-8r2j

References

Patch 1

Advisory 1

Other 1

  • TI-2025-08922 DCMTK dcm2img diybrpxt.h memory corruption CVSS 4.0MEDIUM 4.8
  • TI-2022-04568 DCMTK dcmqrscp dcmqrcnf.cc readPeerList null pointer dereference CVSS 4.0MEDIUM 4.8
  • TI-2020-18990 DCMTK dcmqrscp parseQuota stack-based overflow CVSS 4.0MEDIUM 4.8
  • TI-2024-22823 dcmnet in DCMTK before 3.6.9 has a segmentation fault via an invalid DIMSE message. CVSS 3.1MEDIUM 4.3
  • TI-2019-16028 Out-of-bounds write in OFFIS.de DCMTK CVSS 3.1CRITICAL 9.8
  • TI-2022-01961 OFFIS DCMTK Path Traversal CVSS 3.1CRITICAL 9.8
See all 23 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences