CVE-2021-1616

published 2021-09-23

CVE-2021-1616: A vulnerability in the H.323 application level gateway (ALG) used by the Network Address Translation (NAT) feature of Cisco IOS XE Software could allow an…

Priority P4 26 medium 4.7 CVSS 3.1

AV N AC L PR N UI R S C C N I L A N

A vulnerability in the H.323 application level gateway (ALG) used by the Network Address Translation (NAT) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass the ALG. This vulnerability is due to insufficient data validation of traffic that is traversing the ALG. An attacker could exploit this vulnerability by sending crafted traffic to a targeted device. A successful exploit could allow the attacker to bypass the ALG and open connections that should not be allowed to a remote device located behind the ALG. Note: This vulnerability has been publicly discussed as NAT Slipstreaming.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
cisco	cisco_ios_xe_software	—	—
cisco	ios_xe	< 17.6.1	17.6.1
cisco	ios_xe	—	—

CVSS provenance

nvd v3.1 4.7 MEDIUM CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N

nvd v2.0 4.3 MEDIUM AV:N/AC:M/Au:N/C:N/I:P/A:N

vendor_cisco 4.7 MEDIUM

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