Medium severity · published Mar 10, 2021
CVE-2021-21375
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
6.5
CVSS
2.1%
EPSS
No
On KEV
Description
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 PJSIP version 2.10 and earlier, after an initial INVITE has been sent, when two 183 responses are received, with the first one causing negotiation failure, a crash will occur. This results in a denial of service.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.1% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
PJ
Pjsip · Teluu
through 2.10 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21375
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21375
Patch
https://github.com/pjsip/pjproject/commit/97b3d7addbaa720b7ddb0af9bf6f3e443e664365
Exploit
https://github.com/pjsip/pjproject/security/advisories/GHSA-hvq6-f89p-frvp
Mailing List
https://lists.debian.org/debian-lts-announce/2021/04/msg00023.html
Mailing List
https://lists.debian.org/debian-lts-announce/2021/05/msg00020.html
Third Party Advisory
https://security.gentoo.org/glsa/202107-42
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