CVE-2023-21803

CVEs › CVE-2023-21803

Description

Windows iSCSI Discovery Service Remote Code Execution Vulnerability

Overview

State: PUBLISHED
Assigner (CNA): microsoft
CVSS severity: CRITICAL
CVSS score: 9.8 / 10
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Effective score: 9.8 / 10 CRITICAL source: CNA overview
MSRC score: 9.8 / 10 CRITICAL MS rating: Critical · Remote Code Execution
CWE(s): CWE-190
Reserved: 2022-12-16
Published: 2023-02-14 08:00 UTC
Last updated: 2023-02-14 08:00 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2023/21xxx/CVE-2023-21803.json
Linked Threat: CVE-2023-21803 — Windows iSCSI Discovery Service Remote Code Execution Vulnerability

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2023-25970
Assigner: microsoft
Published: Feb 14, 2023, 7:33:08 PM
Updated: Jan 1, 2025, 12:40:59 AM
EUVD base score (CVSS 3.1): 9.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
EUVD-reported EPSS: 13.9300
Vendors: Microsoft
Products: Windows 10 Version 20H2 (10.0.0 <10.0.19042.2604)

Windows Server 2008 Service Pack 2 (Server Core installation) (6.0.6003.0 <6.0.6003.21915)

Windows 10 Version 22H2 (10.0.19045.0 <10.0.19045.2604)

Windows 10 Version 1607 (10.0.14393.0 <10.0.14393.5717)

Windows 10 Version 1507 (10.0.10240.0 <10.0.10240.19747)

Windows 10 Version 1809 (10.0.17763.0 <10.0.17763.4010)

Windows 10 Version 21H2 (10.0.19043.0 <10.0.19044.2604)

Windows Server 2008 Service Pack 2 (6.0.6003.0 <6.0.6003.21915)
Aliases: GHSA-rjwv-mm96-c3w9

ENISA description: Windows iSCSI Discovery Service Remote Code Execution Vulnerability

EUVD references (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21803

Microsoft Security Response Center MSRC

Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-08-11 01:49 UTC (source: CVRF).

MS severity: Critical
Impact: Remote Code Execution
MS CVSS base score: 9.8 / 10 (temporal 8.5)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Exploit assessment: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely;DOS:N/A
Release: 2023-Feb

Microsoft remediations / KB articles (12)

5022840 — Vendor Fix / Security Update (fixed build 10.0.17763.4010)
5022840 — Update
5022834 — Vendor Fix / Security Update (fixed build 10.0.19042.2604)
5022834 — Update
5022858 — Vendor Fix / Security Update (fixed build 10.0.10240.19747)
5022838 — Vendor Fix / Security Update (fixed build 10.0.14393.5717)
5022890 — Vendor Fix / Monthly Rollup (fixed build 6.0.6003.21915)
5022890 — Update
5022893 — Vendor Fix / Security Only (fixed build 6.0.6003.21915)
5022893 — Update
The following <a href="https://technet.microsoft.com/library/security/dn848375.aspx">mitigating factors</a> may be helpful in your situation: By default the iSCSI Initiator client application is disabled, in this state an attacker cannot exploit this vulnerability. For a system to be vulnerable, the iSCSI Initiator client application would need to be enabled. — Mitigation
The following <a href="https://technet.microsoft.com/library/security/dn848375.aspx">mitigating factors</a> might be helpful in your situation: Only x86 or 32-bit based versions of Windows are affected by this vulnerability. — Mitigation

Microsoft FAQ (1)

How could an attacker exploit the vulnerability?

An attacker could exploit the vulnerability by sending a specially crafted malicious DHCP discovery request to the iSCSI Discovery Service on 32-bit machines. An attacker who successfully exploited the vulnerability could then gain the ability to execute code on the target system.

Affected products (8)

Vendor	Product	Versions	Platforms
Microsoft	Windows 10 Version 1809	`10.0.17763.0` (affected)	32-bit Systems
Microsoft	Windows 10 Version 20H2	`10.0.0` (affected)	32-bit Systems
Microsoft	Windows 10 Version 21H2	`10.0.19043.0` (affected)	32-bit Systems
Microsoft	Windows 10 Version 22H2	`10.0.19045.0` (affected)	32-bit Systems
Microsoft	Windows 10 Version 1507	`10.0.10240.0` (affected)	32-bit Systems
Microsoft	Windows 10 Version 1607	`10.0.14393.0` (affected)	32-bit Systems
Microsoft	Windows Server 2008 Service Pack 2	`6.0.6003.0` (affected)	32-bit Systems
Microsoft	Windows Server 2008 Service Pack 2 (Server Core installation)	`6.0.6003.0` (affected)	32-bit Systems

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

Windows iSCSI Discovery Service Remote Code Execution Vulnerability vendor-advisory

Web references (16)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

5022834 msrc
5022838 msrc
5022840 msrc
5022858 msrc
5022890 msrc
5022893 msrc
5022890 msrc
5022893 msrc
MSRC update guide: CVE-2023-21803 msrc
https://www.cve.org/CVERecord?id=CVE-2023-21803 rapid7:www.cve.org
https://attackerkb.com/topics/CVE-2023-21803 rapid7:attackerkb.com
https://support.microsoft.com/help/5022834 rapid7:support.microsoft.com
https://support.microsoft.com/help/5022838 rapid7:support.microsoft.com
https://support.microsoft.com/help/5022840 rapid7:support.microsoft.com
https://support.microsoft.com/help/5022858 rapid7:support.microsoft.com
http://cwe.mitre.org/data/definitions/190.html rapid7:cwe.mitre.org

Remediations (14)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Mitigate RedSun Zero-Day Without A Patch | Qualys

web:blog.qualys.com

Key Takeaways RedSun is a critical zero-day vulnerability in Microsoft Defender that allows low-privileged users to gain SYSTEM access No patch is currently available, leaving all Defender-enabled Windows systems potentially exposed Qualys VMDR detects affected assets instantly (QID 92382) TruRisk™ Eliminate enables immediate mitigation , removing exploitability without waiting for a fix ...

2026-06-03 23:46 UTC
NVD - Home

web:nvd.nist.gov

The NVD is the U.S. government repository of standards based vulnerability management data represented using the Security Content Automation Protocol (SCAP). This data enables automation of vulnerability management, security measurement, and compliance. The NVD includes databases of security checklist references, security-related software flaws, product names, and impact metrics. For ...

2026-06-03 23:46 UTC
VMware ESXi 8.0 Update 3d Release Notes

web:techdocs.broadcom.com

Patch Category Security Patch Severity Critical Host Reboot Required Yes Virtual Machine Migration or Shutdown Required Yes Affected Hardware N/A Affected Software N/A Affected VIBs Included VMware_bootbank_esxio-update_8..3-.60.24585383 VMware_bootbank_loadesxio_8..3-.60.24585383 PRs Fixed N/A CVE numbers N/A Due to their dependency on the ...

2026-06-03 23:46 UTC
Microsoft Technical Security Notifications

web:www.microsoft.com

Security Update Guide Notifications Microsoft's free Security Update Guide Notifications provide links to security-related software updates and notification of re-released security updates. These notifications are sent via email throughout the month as needed.

2026-06-03 23:46 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-22 05:47 UTC
Vulnerability Remediation vs Mitigation: Which Strategy Wins in ...

web:securityboulevard.com

Organizations must decide how to tackle vulnerabilities—through remediation , mitigation , or a combination of both. But which strategy is more effective? This blog explores the nuances of vulnerability remediation vs mitigation , their respective benefits, and how to choose the right approach.

2026-05-22 05:47 UTC
Android Security Bulletins - Android Open Source Project

web:source.android.com

This Section contains the available Android Security Bulletins, which provide fixes for possible issues affecting Android devices.

2026-05-22 05:47 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-22 05:47 UTC
Google Translate

web:translate.google.com

Google's service, offered free of charge, instantly translates words, phrases, and web pages between English and over 100 other languages.

2026-05-22 05:47 UTC
Microsoft March 2026 Patch Tuesday fixes 2 zero-days, 79 flaws

web:www.bleepingcomputer.com

Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.

2026-05-22 05:47 UTC
Mitigate vs Remediate: Understanding the Difference and Best ... - Emagined

web:www.emagined.com

Discover the difference between mitigation and remediation in vulnerability management. Learn best practices for Pentest remediation and effective cyber protection.

2026-05-22 05:47 UTC
Critical n8n Flaw Expose Automation Nodes to Full RCE

web:cyberpress.org

Three critical vulnerabilities have been disclosed in n8n, the popular open-source workflow automation platform, any one of which could allow an authenticated attacker to achieve remote code execution (RCE) or read arbitrary files from the host server.

2026-05-22 05:47 UTC
Microsoft Patch Tuesday May 2026 - 120 Vulnerabilities Fixed, Including ...

web:cybersecuritynews.com

Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.

2026-05-22 05:47 UTC
Resolving Sweet32, Birthday Attacks on Windows Servers Via GPO

web:www.experts-exchange.com

Learn more about Resolving Sweet32, Birthday Attacks on Windows Servers Via GPO from the expert community at Experts Exchange

2026-05-22 05:47 UTC

AI Forensic Analysis

Only Available for Registered Users. Sign in to view.

Raw JSON

The full cvelistV5 record. Download as CVE-2023-21803.json.

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2023-21803",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-07-23T18:48:13.868553Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-07-23T18:48:18.471Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T09:51:50.915Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "name": "Windows iSCSI Discovery Service Remote Code Execution Vulnerability",
            "tags": [
              "vendor-advisory",
              "x_transferred"
            ],
            "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21803"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows 10 Version 1809",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "10.0.17763.4010",
              "status": "affected",
              "version": "10.0.17763.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows 10 Version 20H2",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "10.0.19042.2604",
              "status": "affected",
              "version": "10.0.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows 10 Version 21H2",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "10.0.19044.2604",
              "status": "affected",
              "version": "10.0.19043.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows 10 Version 22H2",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "10.0.19045.2604",
              "status": "affected",
              "version": "10.0.19045.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows 10 Version 1507",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "10.0.10240.19747",
              "status": "affected",
              "version": "10.0.10240.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows 10 Version 1607",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "10.0.14393.5717",
              "status": "affected",
              "version": "10.0.14393.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows Server 2008 Service Pack 2",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "6.0.6003.21915",
              "status": "affected",
              "version": "6.0.6003.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "32-bit Systems"
          ],
          "product": "Windows Server 2008 Service Pack 2 (Server Core installation)",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "6.0.6003.21915",
              "status": "affected",
              "version": "6.0.6003.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*",
                  "versionEndExcluding": "10.0.17763.4010",
                  "versionStartIncluding": "10.0.17763.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_10_20H2:*:*:*:*:*:*:x86:*",
                  "versionEndExcluding": "10.0.19042.2604",
                  "versionStartIncluding": "10.0.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_10_21H2:*:*:*:*:*:*:x86:*",
                  "versionEndExcluding": "10.0.19044.2604",
                  "versionStartIncluding": "10.0.19043.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_10_22H2:*:*:*:*:*:*:x86:*",
                  "versionEndExcluding": "10.0.19045.2604",
                  "versionStartIncluding": "10.0.19045.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:x86:*",
                  "versionEndExcluding": "10.0.10240.19747",
                  "versionStartIncluding": "10.0.10240.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*",
                  "versionEndExcluding": "10.0.14393.5717",
                  "versionStartIncluding": "10.0.14393.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_server_2008_sp2:*:*:*:*:*:*:x64:*",
                  "versionEndExcluding": "6.0.6003.21915",
                  "versionStartIncluding": "6.0.6003.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:microsoft:windows_server_2008_sp2:*:*:*:*:*:*:x64:*",
                  "versionEndExcluding": "6.0.6003.21915",
                  "versionStartIncluding": "6.0.6003.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "datePublic": "2023-02-14T08:00:00.000Z",
      "descriptions": [
        {
          "lang": "en-US",
          "value": "Windows iSCSI Discovery Service Remote Code Execution Vulnerability"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en-US",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-190",
              "description": "CWE-190: Integer Overflow or Wraparound",
              "lang": "en-US",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-01-01T00:40:59.243Z",
        "orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
        "shortName": "microsoft"
      },
      "references": [
        {
          "name": "Windows iSCSI Discovery Service Remote Code Execution Vulnerability",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21803"
        }
      ],
      "title": "Windows iSCSI Discovery Service Remote Code Execution Vulnerability"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
    "assignerShortName": "microsoft",
    "cveId": "CVE-2023-21803",
    "datePublished": "2023-02-14T19:33:08.749Z",
    "dateReserved": "2022-12-16T22:13:41.240Z",
    "dateUpdated": "2025-01-01T00:40:59.243Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}