Security readout for executives and security teams
Plain-English summary
CVE-2023-4911 is a Linux local privilege escalation flaw in glibc's dynamic loader. An attacker who already has local access can abuse the GLIBC_TUNABLES environment variable when starting privileged SUID programs to gain elevated privileges. CISA KEV listing makes this an urgent patching item, not a theoretical issue.
Executive priority
Treat as high priority because it enables local attackers to become highly privileged and is in CISA KEV. It is not a remote entry point based on the supplied evidence, but it materially worsens any Linux foothold.
Technical view
The flaw is a CWE-122 buffer overflow in ld.so handling of GLIBC_TUNABLES. The supplied data describes local attack vector, low complexity, low privileges, no user interaction, and high confidentiality, integrity, and availability impact. Red Hat lists affected glibc packages across RHEL 8 and 9 variants, with RHEL 6 and 7 glibc marked unaffected.
Likely exposure
Likely exposure is Linux systems running affected glibc builds, especially listed Red Hat Enterprise Linux 8, 8.6 EUS, 9, 9.0 EUS, and Red Hat Virtualization packages. The source bundle does not indicate remote-only exposure; the attacker needs local access or an existing foothold.
Exploitation context
CISA KEV status supports active exploitation. Public exploit reference is listed, but this analysis does not rely on or describe exploit mechanics. The issue is most relevant after initial compromise, where privilege escalation can turn a limited local account into root-level control.
Researcher notes
Focus triage on glibc ld.so behavior, GLIBC_TUNABLES handling, SUID execution paths, and affected package versions. Do not assume every Linux distribution is affected from this bundle alone; verify against each vendor advisory before scoping or closing exposure.
Mitigation direction
- Apply vendor glibc updates from applicable Red Hat or distribution advisories.
- Prioritize internet-facing, multi-user, developer, and shared Linux servers first.
- Check CISA KEV due dates and internal SLA alignment.
- If updates are unavailable, follow vendor-specific temporary guidance only.
- Review third-party appliance advisories for embedded Linux exposure.
Validation and detection
- Inventory glibc package versions across Linux fleets.
- Map systems to affected Red Hat product/version entries in the source bundle.
- Confirm remediation through package manager advisory status or vendor tooling.
- Check for CISA KEV tracking in vulnerability management records.
- Validate that SUID-heavy shared systems receive priority review.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-122: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2023-4911 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.8 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9redhatVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineredhat
Reported to Red Hat.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Made public.
- CVE publishedCVE Program
The CVE record was published.
- Added to KEVCISA-ADP
CISA Known Exploited Vulnerabilities metadata lists this CVE as known exploited.
- ADP timelineCISA-ADP
CVE-2023-4911 added to CISA KEV
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
- 2023-11-21T00:00:00.000Z: CVE-2023-4911 added to CISA KEV
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2023:5453CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2023:5454CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2023:5455CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2023:5476CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:0033CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2023-4911CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2238352CVE reference, redhat · issue-tracking, x_refsource_REDHAT
- https://www.qualys.com/2023/10/03/cve-2023-4911/looney-tunables-local-privilege-escalation-glibc-ld-so.txtCVE reference, redhat
- https://www.qualys.com/cve-2023-4911/CVE reference, redhat
- https://www.exploit-db.com/exploits/52479CVE reference, CVE
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4DBUQRRPB47TC3NJOUIBVWUGFHBJAFDL/CVE reference, CVE · x_transferred
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DFG4P76UHHZEWQ26FWBXG76N2QLKKPZA/CVE reference, CVE · x_transferred
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NDAQWHTSVOCOZ5K6KPIWKRT3JX4RTZUR/CVE reference, CVE · x_transferred
- https://security.gentoo.org/glsa/202310-03CVE reference, CVE · x_transferred
- https://security.netapp.com/advisory/ntap-20231013-0006/CVE reference, CVE · x_transferred
- https://www.debian.org/security/2023/dsa-5514CVE reference, CVE · x_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-4911CVE reference, CISA-ADP · government-resource
- https://cert-portal.siemens.com/productcert/html/ssa-831302.htmlCVE reference, siemens-SADP
- https://cert-portal.siemens.com/productcert/html/ssa-794697.htmlCVE reference, siemens-SADP
- https://cert-portal.siemens.com/productcert/html/ssa-082556.htmlCVE reference, siemens-SADP
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Heap-based Buffer Overflow
Heap-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.