2016-10 Security Bulletin: JUNOSe: Line Card Reset: processor exception 0x68616c74 (halt) task: scheduler, upon receipt of crafted IPv6 packet (CVE-2016-4925)Product Affected:This issue can affect all E Series routers running an affected release of JUNOSe with IPv6 enabled.
Problem:Receipt of a specifically malformed IPv6 packet processed by the router may trigger a line card reset: processor exception 0x68616c74 (halt) in task: scheduler.  The stack trace will resemble:
-> showCrashDump
last reset: exception 0x68616c74 (halt)
task: scheduler
halter: scheduler
halter PC: 0x8a48e8
halters arg: 0x19e9c28
pc: 0x6af77c: debugDisplay__2Ip +0x160
lr: 0x6af7d4: inetChecksum__FPUcUlUsb +0x40
dar: 0x00000000 cr: 0x42020042 xer: 0x20000000 fpcsr: 0x00000000
msr: 0x00009012 dsisr: 0x00000000 ctr: 0x00000000

The line card will reboot and recover without user interaction.  However, additional specifically malformed packets may cause follow-on line card resets and lead to an extended service outage.This issue only affects E Series routers with IPv6 licensed and enabled.  Routers not configured to process IPv6 traffic are unaffected by this vulnerability.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-2016-4925.
Solution:JUNOSe releases containing the fix specifically include: 10.3.3p0-15, 12.3.3p0-6, 13.3.3p0-1, 14.3.2, 15.1.0, and all subsequent releases.  Hotfixes are also available upon request.This issue is being tracked as CQ 97413 and is visible on the Customer Support website.KB16765 – “In which releases are vulnerabilities fixed?” describes which release vulnerabilities are fixed as per our End of Engineering and End of Life support policies.
Workaround:No known workaround exists for this issue.
Implementation: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.Modification History:
2016-10-12: Initial publication

Related Links:CVSS Score:7.5 (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Risk Level:High
Risk Assessment:Information for how Juniper Networks uses CVSS can be found at KB 16446 “Common Vulnerability Scoring System (CVSS) and Juniper’s Security Advisories.”
Acknowledgements:

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