CriticalFix available
pjproject — security advisory
PJSIP is a free and open source multimedia communication library written in C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In affected versions if the incoming STUN message contains an ERROR-CODE attribute, the header length is not checked before performing a subtraction operation, potentially resulting in an integer underflow scenario. This issue affects all users that use STUN. A malicious actor located within the victim’s network may forge and send a specially crafted UDP (STUN) message that could remotely execute arbitrary code on the victim’s machine. Users are advised to upgrade as soon as possible. There are no known workarounds.
- Products
- pjproject
- Affected versions
- Not specified
- Fixed versions
- 2.12-r0
- CVEs
- CVE-2021-37706
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 22:06 UTC · Revision 1
Source evidence
PJSIP is a free and open source multimedia communication library written in C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In affected versions if the incoming STUN message contains an ERROR-CODE attribute, the header length is not checked before performing a subtraction operation, potentially resulting in an integer underflow scenario. This issue affects all users that use STUN. A malicious actor located within the victim’s network may forge and send a specially crafted UDP (STUN) message that could remotely execute arbitrary code on the victim’s machine. Users are advised to upgrade as soon as possible. There are no known workarounds.
osv:ALPINE-CVE-2021-37706
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
pjproject
Fixed versions: 2.12-r0
Complete source record
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"url": "https://osv.dev/vulnerability/ALPINE-CVE-2021-37706",
"method": "structured",
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"title": "ALPINE-CVE-2021-37706",
"summary": "PJSIP is a free and open source multimedia communication library written in C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In affected versions if the incoming STUN message contains an ERROR-CODE attribute, the header length is not checked before performing a subtraction operation, potentially resulting in an integer underflow scenario. This issue affects all users that use STUN. A malicious actor located within the victim’s network may forge and send a specially crafted UDP (STUN) message that could remotely execute arbitrary code on the victim’s machine. Users are advised to upgrade as soon as possible. There are no known workarounds.",
"evidence": "osv:ALPINE-CVE-2021-37706",
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"aliases": [
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"metrics": [
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],
"modified": "2026-10-23T17:17:56.204349315Z",
"provider": "osv",
"upstream": [
"CVE-2021-37706"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2021-37706"
]
},
"related_cves": [
{
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"evidence": "/upstream"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 415514,
"published_at": "2021-12-22T18:15:07.487+00:00"
}