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VulnerabilityCVE-2023-34048Published 2023-10-25

CVE-2023-34048 — Vmware Vcenter Server

criticalCISA KEVPublic exploit1 PoC repoNuclei template

As of 2025-10-21, CVE-2023-34048 is a CRITICAL-severity vulnerability in Vmware Vcenter Server, CVSS v3.1 9.8, EPSS 99.4% (99.9th percentile). It is listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-01-22), with a US federal remediation deadline of 2024-02-12. Threadlinqs Intelligence links 2 tracked threat campaigns to CVE-2023-34048, most recently “UNC3886 Zero-Day Rootkit Campaign Targeting Singaporean Telecommunications — ORB Network C2, Fortinet/VMware Exploitation, Covert Infrastructure Persistence”.

CVSS v3.1
9.8/10Critical
EPSS
99.4%Higher than 99.9% of scored CVEs
CISA KEV
ListedAdded · due 2024-02-12
Tracked threats
2Campaigns referencing it
Priority
9/10Threadlinqs triage score
Published
Updated 2025-10-21
CVSS v3.1 9.8 (CRITICAL) · EPSS 99.4% (higher than 99.9% of all scored CVEs) · Priority 9/10 · Published 2023-10-25

Last updated:

What is CVE-2023-34048?

vCenter Server contains an out-of-bounds write vulnerability in the implementation of the DCERPC protocol. A malicious actor with network access to vCenter Server may trigger an out-of-bounds write potentially leading to remote code execution.

The record classifies CVE-2023-34048 under weakness class CWE-787. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity, availability. 37 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 1100 days ago.

Severity and exploitation probability

CVSS v3.1 base score
9.8 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (FIRST)
99.4% probability of exploitation in the next 30 days, higher than 99.9% of all scored CVEs
CISA KEV
Listed since 2024-01-22, federal remediation deadline 2024-02-12
Threadlinqs priority
9/10 — CISA KEV-listed, which Threadlinqs floors at 9
Published
2023-10-25, last modified 2025-10-21

Is CVE-2023-34048 being exploited?

CISA added CVE-2023-34048 to the Known Exploited Vulnerabilities catalog on 2024-01-22, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2024-02-12 under BOD 22-01. Weaponised exploit code for CVE-2023-34048 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. A ProjectDiscovery Nuclei detection template exists (http/cves/2023/CVE-2023-34048.yaml). It currently carries a trending score of 50 in the Threadlinqs vulnerability feed.

Affected products and versions

  • Vmware: Vcenter Server, Vcenter Server 7.0, Vcenter Server 8.0

Showing 3 of 37 recorded product entries.

How to fix CVE-2023-34048

The record marks a vendor fix as available for CVE-2023-34048. Patch reference: https://www.vmware.com/security/advisories/VMSA-2023-0023.html. Vendor advisory: https://www.vmware.com/security/advisories/VMSA-2023-0023.html. Because CVE-2023-34048 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2024-02-12. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

Threat activity tracking CVE-2023-34048

2 tracked threats in the Threadlinqs corpus reference CVE-2023-34048, either in the campaign’s CVE list or as an indicator on the campaign record.

Sources

Enriched from CVE.org, NVD, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories, ProjectDiscovery Nuclei. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.

Other references