CVE-2021-26713

published 2021-02-19

CVE-2021-26713: A stack-based buffer overflow in res_rtp_asterisk.c in Sangoma Asterisk before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk…

Priority P3 36 medium 6.5 CVSS 3.1

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

A stack-based buffer overflow in res_rtp_asterisk.c in Sangoma Asterisk before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6 allows an authenticated WebRTC client to cause an Asterisk crash by sending multiple hold/unhold requests in quick succession. This is caused by a signedness comparison mismatch.

Affected

17 ranges

Vendor	Product	Version range	Fixed in
debian	asterisk	—	—
digium	asterisk	>= 0 < 16.16.1-r0	16.16.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 0 < 18.2.1-r0	18.2.1-r0
digium	asterisk	>= 16.0.0 < 16.16.1	16.16.1
digium	asterisk	>= 17.0.0 < 17.9.2	17.9.2
digium	asterisk	>= 18.0.0 < 18.2.1	18.2.1
digium	certified_asterisk	—	—

CVSS provenance

nvd v3.1 6.5 MEDIUM CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd v2.0 4.0 MEDIUM AV:N/AC:L/Au:S/C:N/I:N/A:P

osv 6.5 MEDIUM

vendor_debian 6.5 LOW

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CWE-787