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TI-2021-18376 Aliases CVE-2021-41688GHSA-fwff-cx6h-wxmq

DCMTK through 3.6.6 does not handle memory free properly.

Priority LOW 37CWE-415Published · 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-415 and the CVSS impact.

Summary

DCMTK through 3.6.6 does not handle memory free properly. The object in the program is free but its address is still used in other locations. Sending specific requests to the dcmqrdb program will incur a double free. 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
No
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-2021-41688
  2. 2026-10-03 Alias added: GHSA-fwff-cx6h-wxmq

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