# CVE-2023-4911: Glibc: buffer overflow in ld.so leading to privilege escalation

> CVE-2023-4911: Glibc: buffer overflow in ld.so leading to privilege escalation. CVSS 7.8 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2023-4911
Last updated: 2026-10-14T21:45:37Z

- Published: 2023-10-03 17:25 UTC · Updated: 2026-10-14 21:45 UTC · Assigner: redhat
- CVSS: 7.8 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS: 63.8%, 99th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2023-11-21, federal due date 2023-12-12, ransomware use: Unknown
- CWE: CWE-122

## Description

A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBC\_TUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBC\_TUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.

## CISA required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

## Affected vendors and products

- Red Hat: Red Hat Enterprise Linux 6
- Red Hat: Red Hat Enterprise Linux 7
- Red Hat: Red Hat Enterprise Linux 8
- Red Hat: Red Hat Enterprise Linux 8.6 Extended Update Support
- Red Hat: Red Hat Enterprise Linux 9
- Red Hat: Red Hat Enterprise Linux 9.0 Extended Update Support
- Red Hat: Red Hat Virtualization 4 for Red Hat Enterprise Linux 8
- Siemens: SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
- Siemens: SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
- Siemens: SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
- Siemens: SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-4911)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2023-4911)
- [https://access.redhat.com/errata/RHSA-2023:5453](https://access.redhat.com/errata/RHSA-2023:5453)
- [https://access.redhat.com/errata/RHSA-2023:5454](https://access.redhat.com/errata/RHSA-2023:5454)
- [https://access.redhat.com/errata/RHSA-2023:5455](https://access.redhat.com/errata/RHSA-2023:5455)
- [https://access.redhat.com/errata/RHSA-2023:5476](https://access.redhat.com/errata/RHSA-2023:5476)
- [https://access.redhat.com/errata/RHSA-2024:0033](https://access.redhat.com/errata/RHSA-2024:0033)
- [https://access.redhat.com/security/cve/CVE-2023-4911](https://access.redhat.com/security/cve/CVE-2023-4911)
- [https://bugzilla.redhat.com/show\_bug.cgi?id=2238352](https://bugzilla.redhat.com/show_bug.cgi?id=2238352)
- [https://www.qualys.com/2023/10/03/cve-2023-4911/looney-tunables-local-privilege-escalation-glibc-ld-so.txt](https://www.qualys.com/2023/10/03/cve-2023-4911/looney-tunables-local-privilege-escalation-glibc-ld-so.txt)
- [https://www.qualys.com/cve-2023-4911/](https://www.qualys.com/cve-2023-4911/)

---

_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


---
Canonical: https://rewindex.com/cve/CVE-2023-4911 · Markdown: https://rewindex.com/cve/CVE-2023-4911.md · JSON: https://rewindex.com/api/v1/cves/CVE-2023-4911 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:14:36.957Z