High
libcoap, libcoap2 and 1 more products — security advisory
An issue in obgm and Libcoap v.a3ed466 allows a remote attacker to cause a denial of service via thecoap_context_t function in the src/coap_threadsafe.c:297:3 component.
- Products
- libcoap, libcoap2, libcoap3
- Affected versions
- 4.1.2-1, 4.2.0-2, 4.2.1-1, 4.2.1-1build1, 4.3.0-2, 4.3.0-2build1, 4.3.1-2, 4.3.3-1, 4.3.4-1, 4.3.4-1.1build2, 4.3.4-1.1build3, 4.3.4-1.1build4, 4.3.5-1, 4.3.5-2, 4.3.5-3, 4.3.5-4, 4.3.5-4ubuntu1
- Fixed versions
- Not specified
- CVEs
- CVE-2023-51847
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 01:44 UTC · Revision 1
Source evidence
An issue in obgm and Libcoap v.a3ed466 allows a remote attacker to cause a denial of service via thecoap_context_t function in the src/coap_threadsafe.c:297:3 component.
osv:UBUNTU-CVE-2023-51847
libcoap
Fixed versions: Not specified
libcoap2
Fixed versions: Not specified
libcoap2
Fixed versions: Not specified
libcoap3
Fixed versions: Not specified
libcoap3
Fixed versions: Not specified
libcoap3
Fixed versions: Not specified
libcoap3
Fixed versions: Not specified
libcoap3
Fixed versions: Not specified
Complete source record
{
"id": "9f6357d383c424d6edf0e2140329b30ea13f138ba4a5fe8d401ee8a7bd51fabf",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2023-51847",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2023-51847",
"summary": "An issue in obgm and Libcoap v.a3ed466 allows a remote attacker to cause a denial of service via thecoap_context_t function in the src/coap_threadsafe.c:297:3 component.",
"evidence": "osv:UBUNTU-CVE-2023-51847",
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{
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],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2023-51847",
"aliases": [
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],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
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"affected": [
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"purl": "pkg:deb/ubuntu/libcoap2?arch=source&distro=focal",
"ecosystem": "Ubuntu:20.04:LTS"
},
"versions": [
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"4.2.1-1"
],
"database_specific": {
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},
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}
]
}
},
{
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],
"package": {
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"purl": "pkg:deb/ubuntu/libcoap2?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"4.2.1-1",
"4.2.1-1build1"
],
"database_specific": {
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},
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"purl": "pkg:deb/ubuntu/libcoap3?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
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],
"modified": "2026-10-17T12:57:21.969038157Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2023-51847",
"https://www.cve.org/CVERecord?id=CVE-2023-51847",
"https://github.com/obgm/libcoap/issues/1302"
]
},
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"evidence": "/upstream"
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"security_relevant": true,
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"source_id": "core-osv",
"document_id": 357339,
"published_at": "2024-06-06T22:15:00+00:00"
}