# CVE-2023-4813: Glibc: potential use-after-free in gaih_inet()

Status: published. Published: 2023-09-12. Updated: 2026-11-07.

A flaw has been identified in glibc. In an uncommon situation, the gaih_inet function may use memory that has been freed, resulting in an application crash. This issue is only exploitable when the getaddrinfo function is called and the hosts database in /etc/nsswitch.conf is configured with SUCCESS=continue or SUCCESS=merge.

## Remediation

- workaround: Removing the "SUCCESS=continue" or "SUCCESS=merge" configuration from the hosts database in /etc/nsswitch.conf will mitigate this vulnerability.

Note that, these options are not supported by the hosts database, if they were working before it was because of this bug. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 8 (glibc): ≥ 0:2.28-225.el8_8.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support (glibc): ≥ 0:2.28-189.8.el8_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (glibc): ≥ 0:2.34-60.el9_2.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 (glibc): ≥ 0:2.28-189.8.el8_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (compat-glibc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (glibc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (compat-glibc): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (glibc): Version range not reported. Source: CNA: redhat
- Siemens / SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP
- Siemens / SIPLUS S7-1500 CPU 1518-4 PN/DP MFP: ≥ V3.1.0; < V3.1.5 (affected, custom). Source: ADP: siemens-SADP

## Severity and prioritization

- CVSS 3.1: 5.9 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 1.93% as of 2026-11-06; percentile 80.05%

- SSVC: Not available

- Weaknesses: CWE-416

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2023:5453 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2023:5455 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2023:7409 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-4813 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2237798 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- http://www.openwall.com/lists/oss-security/2023/10/03/8 (ADP: CVE; x_transferred)

- https://access.redhat.com/errata/RHSA-2023:5453 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2023:5455 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2023:7409 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-4813 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2237798 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://security.netapp.com/advisory/ntap-20231110-0003/ (ADP: CVE; x_transferred)

- https://cert-portal.siemens.com/productcert/html/ssa-398330.html (ADP: siemens-SADP)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-4813; retrieved 2026-11-07; source updated 2026-11-07

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-4813; retrieved 2026-11-07; source updated Not reported

Revision: 2555f0e1ff4e041e2fa7c3e943b5446716f741a932a0e9cd6089b04641ba0e96

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