CVE-2019-1686

Cisco ASR 9000 Series Aggregation Services Routers ACL Bypass Vulnerability

Description

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. Affected Cisco IOS XR versions are: Cisco IOS XR Software Release 5.1.1 and later till first fixed. First Fixed Releases: 6.5.2 and later, 6.6.1 and later.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.18%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XR Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-iosxracl vendor advisory
http://www.securityfocus.com/bid/108026 vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2019-1686?
CVE-2019-1686 has been scored as a high severity vulnerability.
How to fix CVE-2019-1686?
To fix CVE-2019-1686, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-1686 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2019-1686 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-1686?
CVE-2019-1686 affects Cisco Cisco IOS XR Software.
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