Critical
Security advisory
In nDPI through 3.2 Stable, the SSH protocol dissector has multiple KEXINIT integer overflows that result in a controlled remote heap overflow in concat_hash_string in ssh.c. Due to the granular nature of the overflow primitive and the ability to control both the contents and layout of the nDPI library's heap memory through remote input, this vulnerability may be abused to achieve full Remote Code Execution against any network inspection stack that is linked against nDPI and uses it to perform network traffic analysis.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2020-11939
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:33 UTC · Revision 1
Source evidence
In nDPI through 3.2 Stable, the SSH protocol dissector has multiple KEXINIT integer overflows that result in a controlled remote heap overflow in concat_hash_string in ssh.c. Due to the granular nature of the overflow primitive and the ability to control both the contents and layout of the nDPI library's heap memory through remote input, this vulnerability may be abused to achieve full Remote Code Execution against any network inspection stack that is linked against nDPI and uses it to perform network traffic analysis.
osv:CVE-2020-11939
Complete source record
{
"id": "1b8aeca2aada4e787f98aeba5a751c0b4ed43af3ed392cab5104d6d4245c6bf8",
"url": "https://osv.dev/vulnerability/CVE-2020-11939",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2020-11939",
"summary": "In nDPI through 3.2 Stable, the SSH protocol dissector has multiple KEXINIT integer overflows that result in a controlled remote heap overflow in concat_hash_string in ssh.c. Due to the granular nature of the overflow primitive and the ability to control both the contents and layout of the nDPI library's heap memory through remote input, this vulnerability may be abused to achieve full Remote Code Execution against any network inspection stack that is linked against nDPI and uses it to perform network traffic analysis.",
"evidence": "osv:CVE-2020-11939",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2020-11939",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
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"affected": [
{
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"repo": "https://github.com/ntop/ndpi",
"type": "GIT",
"events": [
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{
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{
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"source": "CPE_RANGE"
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{
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"source": "REFERENCES_COMMIT"
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"modified": "2026-10-20T13:51:18.841410855Z",
"provider": "osv",
"references": [
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"evidence": "/id"
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"source_id": "core-osv",
"document_id": 388288,
"published_at": "2020-04-23T15:15:14.093+00:00"
}