Memory corruption via unchecked authentication trailer pointer
Published Jun 22, 2023 · Updated Feb 13, 2025
Out-of-bounds write in the DCERPC implementation in VMware vCenter Server 7.0 and 8.0 allows remote attackers to corrupt memory via a crafted packet. In rpc__cn_unpack_hdr, attacker-controlled frag_len and auth_len values calculate authp before the packet buffer, and SWAB_IN_PLACE32 writes through that unchecked pointer. No authentication or user interaction is required, but a DCERPC service on ports 2012, 2014, or 2020 must be reachable.
Summary
What happened
Out-of-bounds write in the DCERPC implementation in VMware vCenter Server 7.0 and 8.0 allows remote attackers to corrupt memory via a crafted packet. In rpc__cn_unpack_hdr, attacker-controlled frag_len and auth_len values calculate authp before the packet buffer, and SWAB_IN_PLACE32 writes through that unchecked pointer. No authentication or user interaction is required, but a DCERPC service on ports 2012, 2014, or 2020 must be reachable.
The record
- CVE
- CVE-2023-20894
- Published
- Jun 22, 2023
- Updated
- Feb 13, 2025
- Vendor
- VMware
- Product
- VMware vCenter Server
- Classifications
- CWE-823, T1210
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 22, 2023CVE publishedPublication date reported by the CVE source.
- Feb 13, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=7.0 <7.0 u3m
- Affected versionversion=8.0 <8.0 U1b
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Cisco Talos DCERPC authentication-trailer crash proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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