CVE-2019-19126

Severity: low (CVSS 3.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-11-19 · updated 2026-10-14
Weakness: CWE-665

Description

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.

Affected products

Canonical Ubuntu Linux: 16.04, 18.04, 19.10
Debian Linux: 10.0
Fedoraproject Fedora: 30, 31
GNU C Library (glibc): before 2.31 — fixed in 2.31

How to fix

Upgrade to a fixed version: GNU C Library (glibc) 2.31. Check the vendor advisory for mitigations.

References

https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4FQ5LC6JOYSOYFPRUZ4S45KL6IP3RPPZ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZFJ5E7NWOL6ROE5QVICHKIOUGCPFJVUH/
https://sourceware.org/bugzilla/show_bug.cgi?id=25204
https://usn.ubuntu.com/4416-1/
https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4FQ5LC6JOYSOYFPRUZ4S45KL6IP3RPPZ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZFJ5E7NWOL6ROE5QVICHKIOUGCPFJVUH/
https://sourceware.org/bugzilla/show_bug.cgi?id=25204
https://usn.ubuntu.com/4416-1/
https://cert-portal.siemens.com/productcert/html/ssa-398330.html

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