CVE-2018-0136 Denial of service in Cisco Aggregation Services Router 9000 Series

High 8.6 Published Updated

Remote attackers can cause denial of service on Cisco ASR 9000 routers by sending crafted IPv6 packets to Trident-based line cards.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
None listed

What is CVE-2018-0136?

CVE-2018-0136 is a high-severity denial of service vulnerability in Cisco Ios Xr, published on 31 Jan 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability in the IPv6 subsystem of Cisco IOS XR Software Release 5.3.4 for the Cisco Aggregation Services Router (ASR) 9000 Series could allow an unauthenticated, remote attacker to trigger a reload of one or more Trident-based line cards, resulting in a denial of service (DoS) condition. The vulnerability is due to incorrect handling of IPv6 packets with a fragment header extension. An attacker could exploit this vulnerability by sending IPv6 packets designed to trigger the issue either to or through the Trident-based line card. A successful exploit could allow the attacker to trigger a reload of Trident-based line cards, resulting in a DoS during the period of time the line card takes to restart. This vulnerability affects Cisco Aggregation Services Router (ASR) 9000 Series when the following conditions are met: The router is running Cisco IOS XR Software Release 5.3.4, and the router has installed Trident-based line cards that have IPv6 configured. A software maintenance upgrade (SMU) has been made available that addresses this vulnerability. The fix has also been incorporated into service pack 7 for Cisco IOS XR Software Release 5.3.4. Cisco Bug IDs: CSCvg46800.

Weakness: CWE-20

Which versions are affected by CVE-2018-0136?

It affects 1 product.

Products include Cisco Ios Xr.

How do I fix CVE-2018-0136?

No fix has been published for CVE-2018-0136 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2018-0136 being exploited?

There is no known exploitation of CVE-2018-0136 in the wild and no public exploit code.

All Cisco Ios Xr vulnerabilities

Sources

Also known as GHSA-4wcf-6qr4-2vx5.

Is CVE-2018-0136 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free