CVE-2021-26717

published 2021-02-18

CVE-2021-26717: An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When…

Priority P3 40 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.

Affected

6 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	>= 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

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd v2.0 5.0 MEDIUM AV:N/AC:L/Au:N/C:N/I:N/A:P

osv 7.5 HIGH

vendor_debian 7.5 HIGH

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