CVE-2019-19126
glibc: LD_PREFER_MAP_32BIT_EXEC not ignored in setuid binaries
Severity
LowRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · November 19, 2019
Updated · October 14, 2026
Description
A vulnerability was discovered in glibc where the LD_PREFER_MAP_32BIT_EXEC environment variable is not ignored when running binaries with the setuid flag on x86_64 architectures. This allows an attacker to force system to utilize only half of the memory (making the system think the software is 32-bit only), thus lowering the amount of memory being used with address space layout randomization (ASLR). The highest threat is confidentiality although the complexity of attack is high. The affected application must already have other vulnerabilities for this flaw to be usable.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.0 · 2.9CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE-20 · Improper Input Validation