A denial of service (DoS) issue has been discovered in Juniper SRX Series products that can be exploited by remote unauthenticated attackers. This issue takes place when a certain malformed packet is translated from IPv6 to IPv4. When this malformed packet is sent to a vulnerable SRX Series device, the flowd process may crash. The issue can be repeatedly exploited to create an extended denial of service condition. Juniper SIRT is not aware of any malicious exploitation of this vulnerability. No other Juniper Networks products or platforms are affected by this issue. This issue has been assigned CVE-2014-3822 .
The following software releases have been updated to resolve this specific issue: Junos OS 11.4R8, 12.1R5, 12.1X44-D20, 12.1X45-D15, 12.1X46-D10, 12.1X47-D10, and all subsequent releases (i.e. all releases built after 12.1X47-D10). This issue is being tracked as PR 747680 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.
If NAT protocol translation from IPv6 to IPv4 is not required, disabling the feature will completely mitigate this issue.