CVE-2021-26906: 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…

PriorityP431medium5.9CVSS 3.1

AVNACHPRNUINSUCNINAH

EPSS

2.55%

83.0th percentile

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.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
debian	asterisk	< asterisk 1:16.16.1~dfsg-1 (bullseye)	asterisk 1:16.16.1~dfsg-1 (bullseye)
digium	asterisk	>= 0 < 1:16.16.1~dfsg-1	1:16.16.1~dfsg-1
digium	asterisk	>= 13.0.0 < 13.38.2	13.38.2
digium	asterisk	>= 16.0.0 < 16.16.1	16.16.1
digium	asterisk	>= 17.0.0 < 17.9.2	17.9.2
digium	asterisk	>= 18.0 < 18.2.1	18.2.1
digium	certified_asterisk	—	—

CVSS provenance

nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:N/A:P

osv5.9MEDIUM

vendor_debian5.9MEDIUM

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