CVE-2016-9644

Name: CVE-2016-9644
Creator: NVD / NIST
Published: 2016-11-28T03:59:18.283+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 1.45%

Last modified Jun 17, 2026

CVE-2016-9644 is a vulnerability of currently unknown severity. The __get_user_asm_ex macro in arch/x86/include/asm/uaccess.h in the Linux kernel 4.4.22 through 4.4.28 contains extended asm statements that are incompatible with the exception table, which allows local users to obtain root access on non-SMEP platforms via a crafted application. NOTE: this vulnerability exists because of incorrect backporting of the CVE-2016-9178 patch to older kernels.. EPSS estimates a 1.45% chance of exploitation in the next 30 days.

Description

The __get_user_asm_ex macro in arch/x86/include/asm/uaccess.h in the Linux kernel 4.4.22 through 4.4.28 contains extended asm statements that are incompatible with the exception table, which allows local users to obtain root access on non-SMEP platforms via a crafted application. NOTE: this vulnerability exists because of incorrect backporting of the CVE-2016-9178 patch to older kernels.

Metrics

EPSS Probability

1.45%

70.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-264

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	4.4.22
Linux	Linux Kernel	4.4.23
Linux	Linux Kernel	4.4.24
Linux	Linux Kernel	4.4.25
Linux	Linux Kernel	4.4.26
Linux	Linux Kernel	4.4.27
Linux	Linux Kernel	4.4.28

References

http://www.openwall.com/lists/oss-security/2016/11/07/4Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/94545
http://www.ubuntu.com/usn/USN-3146-1
http://www.ubuntu.com/usn/USN-3146-2
https://lwn.net/Articles/705220/Product
http://www.openwall.com/lists/oss-security/2016/11/07/4Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/94545
http://www.ubuntu.com/usn/USN-3146-1
http://www.ubuntu.com/usn/USN-3146-2
https://lwn.net/Articles/705220/Product

Timeline

Published: Nov 28, 2016
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2016-9644?

How severe is CVE-2016-9644?

Severity scoring for CVE-2016-9644 is pending analysis. The EPSS model estimates a 1.45% probability of exploitation in the next 30 days.

How do I fix CVE-2016-9644?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2016-9644?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST