Name: CVE-2021-26906: Improper Resource Shutdown or Release
Creator: Rapid7
Published: 2021-02-18T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-26906, CWE-404, CVSS 5.9, EPSS 0.00811

An issue was discovered in res_pjsip_session.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.

CVSS Details

CVSS 3.1 Base Score: 5.9
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade asterisk	Mar 26, 2024	Feb 18, 2021
Debian	—	Upgrade asterisk	Jul 30, 2024	Feb 18, 2021
Freebsd	—	Upgrade asterisk16Upgrade asterisk18Upgrade asterisk13	Dec 10, 2025	Feb 18, 2021
Gentoo Linux	—	Upgrade net-misc/asterisk.	Dec 9, 2024	Feb 18, 2021

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