MediumFix available
asterisk — security advisory
Asterisk is an open source private branch exchange and telephony toolkit. In Asterisk prior to versions 18.20.1, 20.5.1, and 21.0.1; as well as certified-asterisk prior to 18.9-cert6; Asterisk is susceptible to a DoS due to a race condition in the hello handshake phase of the DTLS protocol when handling DTLS-SRTP for media setup. This attack can be done continuously, thus denying new DTLS-SRTP encrypted calls during the attack. Abuse of this vulnerability may lead to a massive Denial of Service on vulnerable Asterisk servers for calls that rely on DTLS-SRTP. Commit d7d7764cb07c8a1872804321302ef93bf62cba05 contains a fix, which is part of versions 18.20.1, 20.5.1, 21.0.1, amd 18.9-cert6.
- Products
- asterisk
- Affected versions
- Not specified
- Fixed versions
- 18.20.2-r0, 20.5.1-r0
- CVEs
- CVE-2023-49786
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 15:04 UTC · Revision 1
Source evidence
Asterisk is an open source private branch exchange and telephony toolkit. In Asterisk prior to versions 18.20.1, 20.5.1, and 21.0.1; as well as certified-asterisk prior to 18.9-cert6; Asterisk is susceptible to a DoS due to a race condition in the hello handshake phase of the DTLS protocol when handling DTLS-SRTP for media setup. This attack can be done continuously, thus denying new DTLS-SRTP encrypted calls during the attack. Abuse of this vulnerability may lead to a massive Denial of Service on vulnerable Asterisk servers for calls that rely on DTLS-SRTP. Commit d7d7764cb07c8a1872804321302ef93bf62cba05 contains a fix, which is part of versions 18.20.1, 20.5.1, 21.0.1, amd 18.9-cert6.
osv:ALPINE-CVE-2023-49786
asterisk
Fixed versions: 18.20.2-r0
asterisk
Fixed versions: 18.20.2-r0
asterisk
Fixed versions: 18.20.2-r0
asterisk
Fixed versions: 20.5.1-r0
asterisk
Fixed versions: 20.5.1-r0
asterisk
Fixed versions: 20.5.1-r0
asterisk
Fixed versions: 20.5.1-r0
asterisk
Fixed versions: 20.5.1-r0
asterisk
Fixed versions: 20.5.1-r0
Complete source record
{
"id": "2f959da125a79a9c78dad1814c2ed5328cc3c4869a08a369438bea7b1b5f675a",
"url": "https://osv.dev/vulnerability/ALPINE-CVE-2023-49786",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "ALPINE-CVE-2023-49786",
"summary": "Asterisk is an open source private branch exchange and telephony toolkit. In Asterisk prior to versions 18.20.1, 20.5.1, and 21.0.1; as well as certified-asterisk prior to 18.9-cert6; Asterisk is susceptible to a DoS due to a race condition in the hello handshake phase of the DTLS protocol when handling DTLS-SRTP for media setup. This attack can be done continuously, thus denying new DTLS-SRTP encrypted calls during the attack. Abuse of this vulnerability may lead to a massive Denial of Service on vulnerable Asterisk servers for calls that rely on DTLS-SRTP. Commit d7d7764cb07c8a1872804321302ef93bf62cba05 contains a fix, which is part of versions 18.20.1, 20.5.1, 21.0.1, amd 18.9-cert6.",
"evidence": "osv:ALPINE-CVE-2023-49786",
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{
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},
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{
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"evidence": "/affected/0/ranges"
}
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{
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{
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},
{
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{
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},
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"fixed_versions": [
{
"value": "20.5.1-r0",
"evidence": "/affected/6/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/7/package/name"
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{
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"evidence": "/affected/7/ranges"
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"affected_versions": []
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{
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"fixed_versions": [
{
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"evidence": "/affected/8/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "ALPINE-CVE-2023-49786",
"aliases": [
"ALPINE-CVE-2023-49786"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "19.0.0"
},
{
"fixed": "18.20.2-r0"
}
]
}
],
"package": {
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"purl": "pkg:apk/alpine/asterisk?arch=source",
"ecosystem": "Alpine:v3.16"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-49786.json"
},
"ecosystem_specific": {}
},
{
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"package": {
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"ecosystem": "Alpine:v3.17"
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"ecosystem": "Alpine:v3.18"
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"ecosystem": "Alpine:v3.19"
},
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"package": {
"name": "asterisk",
"purl": "pkg:apk/alpine/asterisk?arch=source",
"ecosystem": "Alpine:v3.22"
},
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],
"package": {
"name": "asterisk",
"purl": "pkg:apk/alpine/asterisk?arch=source",
"ecosystem": "Alpine:v3.23"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-49786.json"
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{
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],
"package": {
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"ecosystem": "Alpine:v3.24"
},
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},
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}
],
"modified": "2026-10-26T17:17:58.658039403Z",
"provider": "osv",
"upstream": [
"CVE-2023-49786"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2023-49786"
]
},
"related_cves": [
{
"value": "CVE-2023-49786",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 454565,
"published_at": "2023-12-14T20:15:52.927+00:00"
}