CVE-2021-32686
Denial of Service in PJSIP
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
5.9
Denial of Service in PJSIP
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
CVE-2021-32686- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-362
- Updated
- 2026-11-02
EUVDEUVD-2021-19490
5.9
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
EUVD-2021-19490- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
NVD
5.9
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
CVE-2021-32686- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:N/A:P - Weakness
- CWE-362
- Updated
- 2026-11-02
OSVALPINE-CVE-2021-32686
5.9
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
ALPINE-CVE-2021-32686- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSV
5.9
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
CVE-2021-32686- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2021-32686
5.9
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
DEBIAN-CVE-2021-32686- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-32686
5.9
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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.
- Record
UBUNTU-CVE-2021-32686- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVMGASA-2021-0559 No score
Updated pjproject packages fix security vulnerability
Updated pjproject packages fix security vulnerability:
In PJSIP before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/ listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service (CVE-2021-32686).
- Record
MGASA-2021-0559- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pjprojectAlpine:v3.14 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.15 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.16 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.17 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.18 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.19 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.20 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.21 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.22 |
before 2.11.1-r0 | 2.11.1-r0 |
pjprojectAlpine:v3.23 |
before 2.11.1-r0 | 2.11.1-r0 |
Show 9 moreShow less
| Package | Affected | Fixed |
|---|---|---|
pjprojectAlpine:v3.24 |
before 2.11.1-r0 | 2.11.1-r0 |
asteriskDebian:14 |
before 1:16.16.1~dfsg-2, plus listed versions 0.1.11-30.1.11-3woody11:1.0.5-21:1.0.5-41:1.0.6-1 Show 45 moreShow less1:1.0.6-21:1.0.7-11:1.0.7.dfsg.1-11:1.0.7.dfsg.1-21:1.0.7.dfsg.1-2sarge11:1.0.7.dfsg.1-2sarge21:1.0.7.dfsg.1-2sarge31:1.0.7.dfsg.1-2sarge41:1.0.7.dfsg.1-2sarge51:1.0.7.dfsg.1-2sarge61:1.0.9.dfsg-11:1.0.9.dfsg-31:1.0.9.dfsg-41:1.0.9.dfsg-51:1.0.9.dfsg-61:1.2.0-beta1.dfsg-11:1.2.0-beta2.dfsg-11:1.2.0-beta2.dfsg-21:1.2.0-beta2.dfsg-31:1.2.0-rc1.dfsg-11:1.2.0-rc2.dfsg-11:1.2.0.dfsg-11:1.2.0.dfsg-21:1.2.0.dfsg-31:1.2.0.dfsg-41:1.2.0.dfsg-51:1.2.0.dfsg-61:1.2.1.dfsg-11:1.2.1.dfsg-21:1.2.1.dfsg-31:1.2.10.dfsg-11:1.2.10.dfsg-1bpo11:1.2.10.dfsg-21:1.2.10.dfsg-31:1.2.11.dfsg-11:1.2.12.1.dfsg-11:1.2.13~dfsg-11:1.2.13~dfsg-21:1.2.13~dfsg-2etch11:1.2.13~dfsg-2etch21:1.2.13~dfsg-2etch31:1.2.13~dfsg-2etch41:1.2.14~dfsg-11:1.2.14~dfsg-21:1.2.14~dfsg-3 |
1:16.16.1~dfsg-2 |
ringDebian:12 |
before 20230206.0~ds1-1 | 20230206.0~ds1-1 |
pjprojectDebian:9 |
before 2.5.5~dfsg-6+deb9u3, plus listed versions 2.5.5~dfsg-62.5.5~dfsg-6+deb9u12.5.5~dfsg-6+deb9u2 |
2.5.5~dfsg-6+deb9u3 |
ringDebian:11 |
before 20210112.2.b757bac~ds1-1+deb11u1, plus listed versions 20210112.2.b757bac~ds1-1 |
20210112.2.b757bac~ds1-1+deb11u1 |
asteriskDebian:11 |
before 1:16.16.1~dfsg-1+deb11u1, plus listed versions 1:16.16.1~dfsg-11:16.16.1~dfsg-1+deb11u1~bpo10+1 |
1:16.16.1~dfsg-1+deb11u1 |
pjprojectMageia:8 |
before 2.10-5.3.mga8 | 2.10-5.3.mga8 |
pjprojectUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 2.1.0.0.ast20130823-12.1.0.0.ast20130823-1+deb8u1build0.16.04.12.1.0.0.ast20130823-1+deb8u1ubuntu0.1~esm1 |
None known |
pjprojectUbuntu:Pro:18.04:LTS |
before 2.7.2~dfsg-1ubuntu0.1~esm1, plus listed versions 2.6~dfsg-22.7~dfsg-12.7.1~dfsg-12.7.1~dfsg-1build12.7.2~dfsg-1 |
2.7.2~dfsg-1ubuntu0.1~esm1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-32686 is a medium vulnerability (CVSS 5.9) in Teluu Pjsip, published July 23, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.07%, the 81st percentile. Fixed in pjproject 2.11.1-r0.
References
github.com/pjsip/pjproject/security/advisories/GHSA-cv8x-p47p-99wr
github.com/pjsip/pjproject/pull/2716
github.com/pjsip/pjproject/commit/d5f95aa066f878b0aef6a64e60b61e8626e664cd
github.com/pjsip/pjproject/releases/tag/2.11.1
debian.org/security/2021/dsa-4999
lists.debian.org/debian-lts-announce/2022/03/msg00035.html
Show 9 moreShow less
security.gentoo.org/glsa/202210-37
lists.debian.org/debian-lts-announce/2024/09/msg00030.html
security.alpinelinux.org/vuln/CVE-2021-32686
security-tracker.debian.org/tracker/CVE-2021-32686
advisories.mageia.org/MGASA-2021-0559.html
bugs.mageia.org/show_bug.cgi?id=29317
ubuntu.com/security/CVE-2021-32686
cve.org/CVERecord?id=CVE-2021-32686
ubuntu.com/security/notices/USN-8122-1
Left out here: 188 versions. The JSON record has them.