CVE-2021-32686

Denial of Service in PJSIP

Severity Score

5.9

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

PJSIP es una biblioteca de comunicación multimedia gratuita y de código abierto escrita en lenguaje C implementando protocolos basados en estándares como SIP, SDP, RTP, STUN, TURN e ICE. En PJSIP versiones anteriores a 2.11.1, se presentan un par de problemas encontrados en el socket SSL. Primero, una condición de carrera entre la devolución de llamada y la destrucción, debido a que el socket aceptado no tiene bloqueo de grupo. Segundo, el socket SSL parent/listener puede ser destruido durante el handshake. Ambos problemas fueron reportados como ocurridos intermitentemente en conexiones TLS con mucha carga. Causan un bloqueo, resultando en una denegación de servicio. Se han corregido en versión 2.11.1

*Credits: N/A

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-05-12 CVE Reserved
2021-07-22 CVE Published
2024-08-03 CVE Updated
2024-08-25 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CAPEC

References (7)

URL	Tag	Source
https://github.com/pjsip/pjproject/releases/tag/2.11.1	Release Notes
https://github.com/pjsip/pjproject/security/advisories/GHSA-cv8x-p47p-99wr	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/03/msg00035.html	Mailing List

URL	Date	SRC

URL	Date	SRC
https://github.com/pjsip/pjproject/commit/d5f95aa066f878b0aef6a64e60b61e8626e664cd	2022-11-16
https://github.com/pjsip/pjproject/pull/2716	2022-11-16

URL	Date	SRC
https://security.gentoo.org/glsa/202210-37	2022-11-16
https://www.debian.org/security/2021/dsa-4999	2022-11-16

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Teluu Search vendor "Teluu"		Pjsip Search vendor "Teluu" for product "Pjsip"				< 2.11.1 Search vendor "Teluu" for product "Pjsip" and version " < 2.11.1"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				11.0 Search vendor "Debian" for product "Debian Linux" and version "11.0"		-		Affected