Product Affected

This issue can affect all E Series routers running an affected release that are accessible via TCP/IP.
High
7.8 (AV:N/AC:L/Au:N/C:N/I:N/A:C)

Problem


Receipt of a crafted IP packet containing a specifically malformed IP Option sent to the interface or loopback IP address of an E Series router may lead to an SRP reset. In a redundant SRP configuration, the system will recover immediately. However, additional crafted packets may cause follow-on SRP resets and lead to an extended service outage. The memory corruption leading to the SRP reset only occurs when very specific types of corruption are received by the router.

This issue is only affected by IPv4 IP Options. IPv6 is not vulnerable to this issue.

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

No other Juniper Networks products or platforms are affected by this issue.

Solution


JunosE releases containing the fix specifically include: 10.3.3p0-10, 11.2.3, 11.3.3, 12.0.3, 12.1.2, 12.2.1, 12.3.0, and all subsequent releases (i.e. all releases after 12.3.0).

This issue is being tracked as CQ 92185 and is visible on the Customer Support website.

KB16765 [juniper.net] - "In which releases are vulnerabilities fixed?" describes which release vulnerabilities are fixed as per our End of Engineering and End of Life support policies.


How to obtain fixed software:

Security vulnerabilities in JunosE are fixed in the next available Maintenance Release of each supported JunosE version. In some cases, a Maintenance Release is not planned to be available in an appropriate time-frame. For these cases, JunosE patches are made available in order to be more timely. Security Advisory and Security Notices will indicate which Maintenance and patch releases contain fixes for the issues described. Upon request to JTAC, customers will be provided download instructions for a patch release. Although Juniper does not provide formal Release Note documentation for a patch release, a list of resolved defects are published via Patch Release Histories available on the download page.

Workaround

There are three known and effective methods to mitigate an SRP reset due to the processing of malformed IP Options:

  1. Configure 'ip filter-options all' on each interface to discard packets containing IP Options. For example: 
    ERX(config)#interface gigabitEthernet 8/0
ERX(config-if)#ip filter-options all

  2. Configure the default DoS Protection Group to discard all packets with IP Options: 
    ERX(config)#dos-protection-group default
ERX(config-dos-protection)#protocol IpOptionsOther rate 0
ERX(config-dos-protection)#protocol IpOptionsOther burst 0
ERX(config-dos-protection)#protocol IpOptionsRouterAlert rate 0
ERX(config-dos-protection)#protocol IpOptionsRouterAlert burst 0

  3. Apply a control plane policer to protect the SRP from IP Options processing: 
    ERX(config)#control-plane
ERX(config-control-plane)#policer protocol IpOptionsOther rate 0
ERX(config-control-plane)#policer protocol IpOptionsRouterAlert rate 0

Severity Assessment

Information for how Juniper Networks uses CVSS can be found at KB 16446 [juniper.net] "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

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