# CVE-2023-4911 — Red Hat Enterprise Linux 8 **CISA KEV** > As of 2026-07-14, CVE-2023-4911 is a HIGH-severity vulnerability in Red Hat Enterprise Linux 8, CVSS v3.1 7.8, EPSS 81.4% (99.6th percentile). It is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-11-21), with a US federal remediation deadline of 2023-12-12. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2023-4911, most recently “EtherHiding: Blockchain-Based C2 on Polygon Fuels ClickFix Backdoor + Banking-Trojan Extension Campaign Adopted by Criminal, North Korean, and Iran-Linked Actors”. **Last updated:** 2026-07-14 ## What is CVE-2023-4911? 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. The record classifies CVE-2023-4911 under weakness class [CWE-122](https://cwe.mitre.org/data/definitions/122.html). Its CVSS v3 base vector states that the flaw requires local access to the host, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity, availability. 7 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 1085 days ago. ## Severity and exploitation probability - **CVSS v3.1 base score:** 7.8 — HIGH (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`) - **EPSS (FIRST):** 81.4% probability of exploitation in the next 30 days, higher than 99.6% of all scored CVEs - **CISA KEV:** Listed since 2023-11-21, federal remediation deadline 2023-12-12 - **Threadlinqs priority:** 9/10 — CISA KEV-listed, which Threadlinqs floors at 9 - **Published:** 2023-10-03, last modified 2026-07-14 ## Is CVE-2023-4911 being exploited? CISA added CVE-2023-4911 to the Known Exploited Vulnerabilities catalog on 2023-11-21, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2023-12-12 under BOD 22-01. Weaponised exploit code for CVE-2023-4911 is publicly available. 11 public proof-of-concept repositories are tracked for this identifier. It currently carries a trending score of 43 in the Threadlinqs vulnerability feed. - [leesh3288/CVE-2023-4911](https://github.com/leesh3288/CVE-2023-4911) (github) - [RickdeJager/CVE-2023-4911](https://github.com/RickdeJager/CVE-2023-4911) (github) - [chaudharyarjun/LooneyPwner](https://github.com/chaudharyarjun/LooneyPwner) (github) - [hadrian3689/looney-tunables-CVE-2023-4911](https://github.com/hadrian3689/looney-tunables-CVE-2023-4911) (github) - [ruycr4ft/CVE-2023-4911](https://github.com/ruycr4ft/CVE-2023-4911) (github) - [KernelKrise/CVE-2023-4911](https://github.com/KernelKrise/CVE-2023-4911) (github) - [Green-Avocado/CVE-2023-4911](https://github.com/Green-Avocado/CVE-2023-4911) (github) - [Diego-AltF4/CVE-2023-4911](https://github.com/Diego-AltF4/CVE-2023-4911) (github) ## Affected products and versions - **Red Hat**: Enterprise Linux 8, Enterprise Linux 8.6 Extended Update Support, Enterprise Linux 9, Enterprise Linux 9.0 Extended Update Support, Virtualization 4 for Red Hat Enterprise Linux 8, Enterprise Linux 6, Enterprise Linux 7 ## How to fix CVE-2023-4911 Because CVE-2023-4911 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2023-12-12. No vendor patch reference has been recorded for CVE-2023-4911 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise. ## Threat activity tracking CVE-2023-4911 1 tracked threat in the Threadlinqs corpus references CVE-2023-4911, either in the campaign’s CVE list or as an indicator on the campaign record. - [EtherHiding: Blockchain-Based C2 on Polygon Fuels ClickFix Backdoor + Banking-Trojan Extension Campaign Adopted by Criminal, North Korean, and Iran-Linked Actors](https://intel.threadlinqs.com/threat/TL-2026-2273) — HIGH · 2026-09-01 ## Sources Enriched from CVE.org, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-09-01. **Vendor advisory and patch** - [access.redhat.com — vendor advisory](https://access.redhat.com/errata/RHSA-2023:5453) - [access.redhat.com — vendor advisory (RHSA 2023:5454)](https://access.redhat.com/errata/RHSA-2023:5454) - [access.redhat.com — vendor advisory (RHSA 2023:5455)](https://access.redhat.com/errata/RHSA-2023:5455) - [access.redhat.com — vendor advisory (RHSA 2023:5476)](https://access.redhat.com/errata/RHSA-2023:5476) - [access.redhat.com — vendor advisory (RHSA 2024:0033)](https://access.redhat.com/errata/RHSA-2024:0033) **Third-party advisory** - [access.redhat.com — vdb entry](https://access.redhat.com/security/cve/CVE-2023-4911) - [bugzilla.redhat.com — issue tracking](https://bugzilla.redhat.com/show_bug.cgi?id=2238352) **Other references** - [qualys.com](https://www.qualys.com/2023/10/03/cve-2023-4911/looney-tunables-local-privilege-escalation-glibc-ld-so.txt) - [qualys.com (cve 2023 4911)](https://www.qualys.com/cve-2023-4911/) Canonical: https://intel.threadlinqs.com/cve/CVE-2023-4911 Full detection coverage and IOCs for threats exploiting CVE-2023-4911 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp