Brocade Security Advisory

Brocade Security Advisory ID:

BSA-2017-473

 

Risk Impact:

Medium

Initial Publication Date:

November 17, 2017

 

Workaround:

N/A

Last Updated:

 

 

Component:

JBOSS WildFly

Revision:

1.0: Final

 

Affected CVE:

CVE-2017-1000255

 

 

 

CVSS Score:

6.1

Summary

On Linux running on PowerPC hardware (Power8 or later) a user process can craft a signal frame and then do a sigreturn so that the kernel will take an exception (interrupt), and use the r1 value *from the signal frame* as the kernel stack pointer. As part of the exception entry the content of the signal frame is written to the kernel stack, allowing an attacker to overwrite arbitrary locations with arbitrary values. The exception handling does produce an oops, and a panic if panic_on_oops=1, but only after kernel memory has been over written. This flaw was introduced in commit: "5d176f751ee3 (powerpc: tm: Enable transactional memory (TM) lazily for userspace)" which was merged upstream into v4.9-rc1. Please note that kernels built with CONFIG_PPC_TRANSACTIONAL_MEM=n are not vulnerable.

Affected Products

No Brocade products are affected by this vulnerability.

Products Confirmed Not Vulnerable

Brocade Fabric OS and Brocade Network Advisor are confirmed not affected by this vulnerability.

Workaround

There are no workarounds that address this vulnerability.

Revision History

Version

Change

Date

1.0

Initial Publication

November 17, 2017

 

 

 

Disclaimer

THIS DOCUMENT IS PROVIDED ON AN AS-IS BASIS SOLELY FOR INFORMATIONAL PURPOSES AND DOES NOT IMPLY ANY KIND OF GUARANTY OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. YOUR USE OF THE INFORMATION CONTAINED HEREIN IS AT YOUR OWN RISK. ALL INFORMATION PROVIDED HEREIN IS BASED ON BROCADE'S CURRENT KNOWLEDGE AND UNDERSTANDING OF THE VULNERABILITY AND IMPACT TO BROCADE HARDWARE AND SOFTWARE PRODUCTS. BROCADE RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.