CVE-2019-19126

On the x86-64 architecture, the GNU C Library (aka glibc) before 2.31 fails to ignore the LD_PREFER_MAP_32BIT_EXEC environment variable during program execution after a security transition, allowing local attackers to restrict the possible mapping addresses for loaded libraries and thus bypass ASLR for a setuid program.

Weakness

The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.

Affected Software

Name	Vendor	Start Version	End Version
Glibc	Gnu	*	2.31 (excluding)
Red Hat Enterprise Linux 7	RedHat	glibc-0:2.17-317.el7	*
Red Hat Enterprise Linux 8	RedHat	glibc-0:2.28-101.el8	*
Red Hat Enterprise Linux 8	RedHat	glibc-0:2.28-101.el8	*
Red Hat OpenShift Do	RedHat	openshiftdo/odo-init-image-rhel7:1.1.3-2	*
Eglibc	Ubuntu	trusty	*
Glibc	Ubuntu	bionic	*
Glibc	Ubuntu	disco	*
Glibc	Ubuntu	eoan	*
Glibc	Ubuntu	esm-infra/bionic	*
Glibc	Ubuntu	esm-infra/xenial	*
Glibc	Ubuntu	trusty	*
Glibc	Ubuntu	upstream	*
Glibc	Ubuntu	xenial	*

Potential Mitigations

Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
For example, in Java, if the programmer does not explicitly initialize a variable, then the code could produce a compile-time error (if the variable is local) or automatically initialize the variable to the default value for the variable’s type. In Perl, if explicit initialization is not performed, then a default value of undef is assigned, which is interpreted as 0, false, or an equivalent value depending on the context in which the variable is accessed.

NVD	https://nvd.nist.gov/vuln/detail/CVE-2019-19126
CWE	https://cwe.mitre.org/data/definitions/665.html

Improper Initialization

Weakness

Affected Software

Potential Mitigations

References

CVE-2019-19126

Improper Initialization

Weakness

Affected Software

Potential Mitigations

Related Attack Patterns

References