High
Security advisory
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-41688
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 11:57 UTC · Revision 1
Source evidence
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.
osv:CVE-2021-41688
Complete source record
{
"id": "5660793895f2d18b3d7b3abebad5e263f69b782d5c60de814a49e3b2f30836ff",
"url": "https://osv.dev/vulnerability/CVE-2021-41688",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-41688",
"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.",
"evidence": "osv:CVE-2021-41688",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2021-41688",
"aliases": [
"CVE-2021-41688"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/dcmtk/dcmtk",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "6cb30bd7fb42190e0188afbd8cb961c62a6fb9c9"
},
{
"fixed": "a9697dfeb672b0b9412c00c7d36d801e27ec85cb"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:offis:dcmtk:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "3.6.6"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "a9697dfeb672b0b9412c00c7d36d801e27ec85cb"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"DCMTK-3.6.5",
"DCMTK-3.6.6",
"DCMTK-3.6.5+_20191213",
"DCMTK-3.6.4",
"DCMTK-3.6.3",
"DCMTK-3.6.2",
"DCMTK-3.6.1_20170228",
"DCMTK-3.6.1_20161102",
"DCMTK-3.6.1_20160630",
"DCMTK-3.6.1_20160216",
"DCMTK-3.6.1_20150924",
"DCMTK-3.6.1_20150629",
"DCMTK-3.6.1_20150217",
"DCMTK-3.6.1_20140617",
"DCMTK-3.6.1_20131114",
"DCMTK-3.6.1_20121102",
"DCMTK-3.6.1_20120831",
"DCMTK-3.6.1_20120515",
"DCMTK-3.6.1_20120222",
"DCMTK-3.6.1_20111208",
"DCMTK-3.6.1_20110922",
"DCMTK-3.6.1_20110707",
"DCMTK-3.6.1_20110519",
"DCMTK-3.6.1_20110225",
"DCMTK-3.6.0",
"DCMTK-3.5.4",
"DCMTK-3.5.3",
"DCMTK-3.5.2a",
"DCMTK-3.5.2",
"DCMTK-3.5.1",
"DCMTK-3.5.0",
"DCMTK-3.4.2",
"DCMTK-3.4.1",
"DCMTK-3.4.0",
"DCMTK-3.3.1",
"DCMTK-3.3.0",
"DCMTK-3.2.1",
"DCMTK-3.2.0",
"DCMTK-3.1.2",
"DCMTK-3.1.1",
"DCMTK-3.1.0",
"CAR96-3.0.2",
"CAR96-3.0.1"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-41688.json"
}
}
],
"modified": "2026-10-20T10:54:58.898391444Z",
"provider": "osv",
"references": [
"https://lists.debian.org/debian-lts-announce/2024/06/msg00022.html",
"https://lists.debian.org/debian-lts-announce/2025/01/msg00032.html",
"https://github.com/DCMTK/dcmtk/commit/a9697dfeb672b0b9412c00c7d36d801e27ec85cb",
"https://github.com/DCMTK/dcmtk"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-41688",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 386621,
"published_at": "2022-06-28T13:15:10.38+00:00"
}