On SRX Series devices, when NAT protocol translation from IPv4 to IPv6 is enabled, a certain crafted packet may cause the flowd process to hang or crash. A hang or repeated crash of the flowd process constitutes an extended denial of service condition for SRX Series devices. 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-2014-3817 .
The following software releases have been updated to resolve this specific issue: 11.4R12, 12.1X44-D32, 12.1X44-D35, 12.1X45-D25, 12.1X46-D20, 12.1X47-D10, and all subsequent releases (i.e. all releases built after 12.1X47-D10). This issue is being tracked as PR 954437 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 IPv4 to IPv6 is not required, disabling (by deleting the setting or deactivating) the feature will completely mitigate this issue.