cisco-sa-20190417-iosxracl: Cisco ASR 9000 Series Aggregation Services Routers ACL Bypass Vulnerability
A vulnerability in the TCP flags inspection feature for access control lists (ACLs) on Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to bypass protection offered by a configured ACL on an affected device. The vulnerability is due to incorrect processing of the ACL applied to an interface of an affected device when Cisco Express Forwarding load balancing using the 3-tuple hash algorithm is enabled. An attacker could exploit this vulnerability by sending traffic through an affected device that should otherwise be denied by the configured ACL. An exploit could allow the attacker to bypass protection offered by a configured ACL on the affected device. There are workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-iosxracl
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Frequently Asked Questions
What is the severity of cisco-sa-20190417-iosxracl?
The severity of cisco-sa-20190417-iosxracl is considered high due to the potential for unauthenticated remote access.
How do I fix cisco-sa-20190417-iosxracl?
To fix cisco-sa-20190417-iosxracl, update the affected Cisco ASR 9000 Series routers to the patched version provided by Cisco.
What is the impact of cisco-sa-20190417-iosxracl?
The impact of cisco-sa-20190417-iosxracl allows remote attackers to bypass configured access control lists (ACLs) on affected devices.
Which devices are affected by cisco-sa-20190417-iosxracl?
The devices affected by cisco-sa-20190417-iosxracl are Cisco ASR 9000 Series Aggregation Services Routers.
Is authentication required to exploit cisco-sa-20190417-iosxracl?
No, authentication is not required to exploit cisco-sa-20190417-iosxracl, making it particularly concerning.