CVE-2016-9644

Severity: high (CVSS 7.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-11-28 · updated 2026-06-17
Weakness: CWE-264

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.

Affected products

Linux kernel: 4.4.22, 4.4.23, 4.4.24, 4.4.25, 4.4.26, 4.4.27 (+1)

References

http://www.openwall.com/lists/oss-security/2016/11/07/4
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/
http://www.openwall.com/lists/oss-security/2016/11/07/4
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/

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