CVE-2021-26906: Medium severity asterisk vulnerability

Published Feb 18, 2021
·
Updated

An issue was discovered in respjsipsession.c in Digium Asterisk through 13.38.1; 14.x, 15.x, and 16.x through 16.16.0; 17.x through 17.9.1; and 18.x through 18.2.0, and Certified Asterisk through 16.8-cert5. An SDP negotiation vulnerability in PJSIP allows a remote server to potentially crash Asterisk by sending specific SIP responses that cause an SDP negotiation failure.

Affected Software

17 affected components
Asterisk>=13.0.0<13.38.2
Asterisk>=16.0.0<16.16.1
Asterisk>=17.0.0<17.9.2
Asterisk>=18.0<18.2.1
Digium Asterisk Appliance Developer Kit=16.8
Digium Asterisk Appliance Developer Kit=16.8-cert1-rc1
Digium Asterisk Appliance Developer Kit=16.8-cert1-rc2
Digium Asterisk Appliance Developer Kit=16.8-cert1-rc3
Digium Asterisk Appliance Developer Kit=16.8-cert1-rc4
Digium Asterisk Appliance Developer Kit=16.8-cert2
Digium Asterisk Appliance Developer Kit=16.8-cert3
Digium Asterisk Appliance Developer Kit=16.8-cert4
Digium Asterisk Appliance Developer Kit=16.8-cert4-rc1
Digium Asterisk Appliance Developer Kit=16.8-cert4-rc2
Digium Asterisk Appliance Developer Kit=16.8-cert4-rc3
Digium Asterisk Appliance Developer Kit=16.8-cert4-rc4
Digium Asterisk Appliance Developer Kit=16.8-cert5

Event History

Feb 18, 2021
CVE Published
via MITRE·07:50 PM
Data Sourced
via MITRE·07:50 PM
Description
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Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2021-26906.

2

What is the severity of CVE-2021-26906?

The severity of CVE-2021-26906 is medium with a score of 5.9.

3

Which software versions are affected by CVE-2021-26906?

Digium Asterisk versions through 13.38.1, 14.x through 16.16.0, 17.x through 17.9.1, and 18.x through 18.2.0, as well as Certified Asterisk through 16.8-cert5 are affected by CVE-2021-26906.

4

How can a remote server potentially crash Asterisk due to CVE-2021-26906?

An SDP negotiation vulnerability in PJSIP allows a remote server to potentially crash Asterisk.

5

Is there a fix available for CVE-2021-26906?

Yes, please refer to the official Asterisk project security advisory AST-2021-005 and download the necessary patches or updates from the Asterisk downloads page.

Contact

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