CVE-2016-7042: Buffer Overflow
It was found that when gcc stack protector is turned on, prockeysshow() can cause a panic due to stack corruption. This happens because xbuf[] is not big enough to hold a 64-bit timeout rendered as weeks.
Product bug:
https://bugzilla.redhat.com/showbug.cgi?id=1373499
Other sources
It was found that when the gcc stack protector was enabled, reading the /proc/keys file could cause a panic in the Linux kernel due to stack corruption. This happened because an incorrect buffer size was used to hold a 64-bit timeout value rendered as weeks.
The prockeysshow function in security/keys/proc.c in the Linux kernel through 4.8.2, when the GNU Compiler Collection (gcc) stack protector is enabled, uses an incorrect buffer size for certain timeout data, which allows local users to cause a denial of service (stack memory corruption and panic) by reading the /proc/keys file.
Affected Software
Remediation
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is CVE-2016-7042?
CVE-2016-7042 is a vulnerability in the Linux kernel that allows local users to cause a denial of service (stack memory corruption and panic).
What is the severity of CVE-2016-7042?
The severity of CVE-2016-7042 is high with a CVSS score of 5.5.
Which software versions are affected by CVE-2016-7042?
Versions 3.2.0-115.157, 3.13.0-101.148, 4.4.0-47.68, 4.8.0-27.29, and 4.9~ of the Linux kernel for Ubuntu are affected by CVE-2016-7042.
How can I fix CVE-2016-7042?
To fix CVE-2016-7042, update your Linux kernel to version 3.2.0-115.157, 3.13.0-101.148, 4.4.0-47.68, 4.8.0-27.29, or 4.9~.
Where can I find more information about CVE-2016-7042?
More information about CVE-2016-7042 can be found at the following links: [link1](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1373499), [link2](https://access.redhat.com/support/policy/updates/errata/), [link3](https://bugzilla.redhat.com/show_bug.cgi/attachment.cgi?id=1200212&action=diff).