CVE-2021-31878

Gentoo Linux Security Advisory 202412-03

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

An issue was discovered in PJSIP in Asterisk before 16.19.1 and before 18.5.1. To exploit, a re-INVITE without SDP must be received after Asterisk has sent a BYE request.

Se ha detectado un problema en PJSIP en Asterisk versiones anteriores a 16.19.1 y versiones anteriores a 18.5.1. Para explotarlo, se debe recibir un re-INVITE sin SDP después de que Asterisk haya enviado una petición BYE

When Asterisk receives a re-INVITE without SDP after having sent a BYE request a crash will occur. This occurs due to the Asterisk channel no longer being present while code assumes it is.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

Single

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-04-29 CVE Reserved
2021-07-22 CVE Published
2024-08-03 CVE Updated
2024-08-03 First Exploit
2025-05-05 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-617: Reachable Assertion

CAPEC

References (5)

URL	Tag	Source

URL	Date	SRC
https://issues.asterisk.org/jira/browse/ASTERISK-29381	2024-08-03

URL	Date	SRC
http://downloads.asterisk.org/pub/security/AST-2021-007.html	2021-08-07
http://packetstormsecurity.com/files/163638/Asterisk-Project-Security-Advisory-AST-2021-007.html	2021-08-07
http://seclists.org/fulldisclosure/2021/Jul/48	2021-08-07
https://downloads.digium.com/pub/security/AST-2021-007.html	2021-08-07

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Digium Search vendor "Digium"		Asterisk Search vendor "Digium" for product "Asterisk"				16.17.0 Search vendor "Digium" for product "Asterisk" and version "16.17.0"		-		Affected
Digium Search vendor "Digium"		Asterisk Search vendor "Digium" for product "Asterisk"				16.18.0 Search vendor "Digium" for product "Asterisk" and version "16.18.0"		-		Affected
Digium Search vendor "Digium"		Asterisk Search vendor "Digium" for product "Asterisk"				16.19.0 Search vendor "Digium" for product "Asterisk" and version "16.19.0"		-		Affected
Digium Search vendor "Digium"		Asterisk Search vendor "Digium" for product "Asterisk"				18.3.0 Search vendor "Digium" for product "Asterisk" and version "18.3.0"		-		Affected
Digium Search vendor "Digium"		Asterisk Search vendor "Digium" for product "Asterisk"				18.4.0 Search vendor "Digium" for product "Asterisk" and version "18.4.0"		-		Affected
Digium Search vendor "Digium"		Asterisk Search vendor "Digium" for product "Asterisk"				18.5.0 Search vendor "Digium" for product "Asterisk" and version "18.5.0"		-		Affected