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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | glibc | 2.29-8 | — |
| Debian 13 | glibc | 2.29-8 | — |
| Debian 12 | glibc | 2.29-8 | — |
| Debian 10 | glibc | 2.28-10+deb10u2 | DLA-3152-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | glibc | 2.27-3ubuntu1.2 | USN-4416-1 |
| Ubuntu 16.04 LTS | glibc | 2.23-0ubuntu11.2 | USN-4416-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | nscd +212 | 2.28-101.el8 | RHSA-2020:1828 |
| RHEL 7 | nscd +7 | 2.17-317.el7 | RHSA-2020:3861 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | glibc | 2.26-13.36.1 | SUSE-SU-2020:0262-1 |
| SLES 15 | glibc | 2.26-13.36.1 | SUSE-SU-2020:0262-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | glibc | 2.34-1.2 | openSUSE-SU-2024:10792-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | nscd +199 | 2.26-37.amzn2 | ALAS2-2023-2221 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | nscd +211 | 2.28-101.0.1.el8 | ELSA-2020-1828 |
| Oracle Linux 7 | nscd +6 | 2.17-317.0.1.el7 | ELSA-2020-3861 |
Advisories 14
- WID-SEC-2026-4026 Red Hat OpenShift: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 18, 2026
- RHSA-2020:3861 Red Hat Security Advisory: glibc security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- RHSA-2020:1828 Red Hat Security Advisory: glibc security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 14, 2026
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- USN-4416-1 glibc vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DLA-3152-1 glibc - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10792-1 glibc-2.34-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0262-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2024-1186 IBM DB2 REST: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jan 25, 2026
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- WID-SEC-2022-1745 GNU libc: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen BSI CERT-Bund (WID) · Aug 23, 2023
- ALAS2-2023-2221 Moderate: glibc security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Aug 23, 2023
- ELSA-2020-3861 Low: glibc security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 6, 2020
- ELSA-2020-1828 Low: glibc security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 5, 2020
References
- https://sourceware.org/bugzilla/show_bug.cgi?id=25204
- FEDORA-2020-1a3bdfde17 vendor-advisory
- FEDORA-2020-c32e4b271c vendor-advisory
- USN-4416-1 vendor-advisory
- [debian-lts-announce] 20221017 [SECURITY] [DLA 3152-1] glibc security update mailing-list