Threats / VMware / CVE-2023-34048
CVE-2023-34048
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
VMware vCenter Server vulnerability
VMware vCenter Server contains an out-of-bounds write vulnerability in DCERPC protocol implementation enabling remote code execution.
Verdict
Today item — known-exploited.
An unauthenticated attacker can exploit this out-of-bounds write flaw to achieve remote code execution on vCenter Server systems. The high EPSS score and active exploitation in the wild indicate immediate risk to unpatched deployments.
CISA KEV Yes · 2024-01-225EPSS 0.99428 (verify live)6CVSS 9.83CISA SSVC Exploitation: active · Automatable: no · Impact: total4Exploit Public PoC / detection · nuclei template13
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
21 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-01-22).
Probability (EPSS)
EPSS 0.99428 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) · Affected: VMware, vCenter Server. Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 3.1, set at disclosure.
Weakness (CWE)
Mapped to CWE-787 Out-of-bounds Write — weakness family: Memory safety.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 89 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
Public exploit available
Public exploit tooling is catalogued for this CVE (a public proof-of-concept / detection template). Catalog entries: nuclei template. We link the catalog page(s) only — no payload or code is hosted or restated here.Link, never host — the catalog page is the source; basicsecurity.net does not redistribute payloads.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious DCERPC protocol message targeting the vulnerable code path in vCenter Server.
Business
Attackers gain arbitrary code execution capability on critical infrastructure management systems.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I send the exploit payload over the network to trigger the out-of-bounds write condition.
Business
Complete compromise of vCenter Server enables lateral movement across the entire virtualized environment.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute commands with vCenter Server privileges to establish persistence and control.
Business
Attackers can access, modify, or destroy virtual machines and sensitive data across all managed hosts.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05