CVE-2023-21548
published 2023-01-10CVE-2023-21548: Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
PriorityP347high8.1CVSS 3.1
AVNACHPRNUINSUCHIHAH
EPSS
1.08%
61.5th percentile
Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
Affected
38 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_10_version_1507 | >= 10.0.10240.0 < 10.0.10240.19685 | 10.0.10240.19685 |
| microsoft | windows_10_version_1607 | >= 10.0.14393.0 < 10.0.14393.5648 | 10.0.14393.5648 |
| microsoft | windows_10_version_1809 | >= 10.0.0 < 10.0.17763.3887 | 10.0.17763.3887 |
| microsoft | windows_10_version_1809 | >= 10.0.17763.0 < 10.0.17763.3887 | 10.0.17763.3887 |
| microsoft | windows_10_version_20h2 | >= 10.0.0 < 10.0.19042.2486 | 10.0.19042.2486 |
| microsoft | windows_10_version_21h2 | >= 10.0.19043.0 < 10.0.19044.2486 | 10.0.19044.2486 |
| microsoft | windows_10_version_22h2 | >= 10.0.19045.0 < 10.0.19045.2486 | 10.0.19045.2486 |
| microsoft | windows_11_version_21h2 | >= 10.0.0 < 10.0.22000.1455 | 10.0.22000.1455 |
| microsoft | windows_11_version_22h2 | >= 10.0.22621.0 < 10.0.22621.1105 | 10.0.22621.1105 |
| microsoft | windows_7 | >= 6.1.0 < 6.1.7601.26321 | 6.1.7601.26321 |
| microsoft | windows_7_service_pack_1 | >= 6.1.0 < 6.1.7601.26321 | 6.1.7601.26321 |
| microsoft | windows_8.1 | >= 6.3.0 < 6.3.9600.20778 | 6.3.9600.20778 |
| microsoft | windows_server_2008 | — | — |
| microsoft | windows_server_2008_r2_service_pack_1 | >= 6.1.7601.0 < 6.1.7601.26321 | 6.1.7601.26321 |
| microsoft | windows_server_2008_service_pack_2 | >= 6.0.6003.0 < 6.0.6003.21872 | 6.0.6003.21872 |
| microsoft | windows_server_2012 | — | — |
| microsoft | windows_server_2012 | >= 6.2.9200.0 < 6.2.9200.24075 | 6.2.9200.24075 |
| microsoft | windows_server_2012_r2 | >= 6.3.9600.0 < 6.3.9600.20778 | 6.3.9600.20778 |
| microsoft | windows_server_2016 | >= 10.0.14393.0 < 10.0.14393.5648 | 10.0.14393.5648 |
| microsoft | windows_server_2019 | >= 10.0.17763.0 < 10.0.17763.3887 | 10.0.17763.3887 |
| microsoft | windows_server_2022 | >= 10.0.20348.0 < 10.0.20348.1487 | 10.0.20348.1487 |
| msrc | windows_10 | — | — |
| msrc | windows_10_version_1607 | — | — |
| msrc | windows_10_version_1809 | — | — |
| msrc | windows_10_version_20h2 | — | — |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_msrc8.1HIGH
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GHSA
GHSA-8727-xm78-42c7: Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
ghsa_unreviewed·2023-01-11·CVSS 8.1
CVE-2023-21548 [HIGH] GHSA-8727-xm78-42c7: Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability. This CVE ID is unique from CVE-2023-21535.
GHSA
GHSA-43xq-5x33-h3j9: Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
ghsa_unreviewed·2023-01-11·CVSS 8.1
CVE-2023-21535 [HIGH] CWE-362 GHSA-43xq-5x33-h3j9: Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability. This CVE ID is unique from CVE-2023-21548.
Microsoft
Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
vendor_msrc·2023-01-10·CVSS 8.1
CVE-2023-21548 [HIGH] CWE-591 Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution Vulnerability
FAQ: How could an attacker exploit the vulnerability?
To exploit this vulnerability, an attacker would need to send a specially crafted malicious SSTP packet to a SSTP server. This could result in remote code execution on the server side.
FAQ: According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?
Successful exploitation of this vulnerability requires an attacker to win a race condition.
Windows Secure Socket Tunneling Protocol (SSTP): Windows Secure Socket Tunneling Protocol (SSTP)
Microsoft: Microsoft
Customer Action Required: Yes
Impact: Remote Code Execution
Exploit Status: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploita
No detection rules found.
No public exploits indexed.
Talos
Microsoft Patch Tuesday for January 2023 — Snort rules and prominent vulnerabilities
blogs_talos·2023-01-10·CVSS 8.1
CVE-2023-21743 [HIGH] Microsoft Patch Tuesday for January 2023 — Snort rules and prominent vulnerabilities
Microsoft released its monthly security update on Tuesday, disclosing 98 vulnerabilities. Of these vulnerabilities, 11 are classified as “Critical”, 87 are classified as “Important”, no vulnerability classified as “Moderate.”
According to Microsoft all “Critical“ vulnerability are either less likely or unlikely to be exploited, except of the security bypass vulnerability CVE-2023-21743 on Microsoft SharePoint Server machines. This vulnerability has a low complexity and can be easily triggered by an attacker. In a network-based attack, an unauthenticated user could make an anonymous connection to the targeted SharePoint server.
Two of the “Critical“ vulnerabilities, which Microsoft considers to be “less likely” to be exploited due to their complexity are CVE-2023-21535 and CVE-2023-21548.
Qualys
The January 2023 Patch Tuesday Security Update Review | Qualys
blogs_qualys·2023-01-10·CVSS 5.3
CVE-2023-21743 [MEDIUM] The January 2023 Patch Tuesday Security Update Review | Qualys
#### Table of Contents
- Microsoft Patches for January2023
- Adobe Patches for January2023
- Microsoft End of support Product
- Notable and Critical Microsoft Vulnerabilities Patched
- CVE-2023-21743 Microsoft SharePoint Server Security Feature Bypass Vulnerability
- CVE-2023-21763 CVE-2023-21764 Microsoft Exchange Server Elevation of Privilege Vulnerability
- Other Microsoft Vulnerability Highlights
- Microsoft Release Summary
- Discover and Prioritize Vulnerabilities in Vulnerability Management, Detection & Response (VMDR)
- Qualys Monthly Webinar Series
- This Month in Vulnerabilities & Patches
As we enter the first second Tuesday of the year, it is noteworthy that both Microsoft and Adobe have released their latest security updates and fixes. We invite you to join us as we review and
Talos
Microsoft Patch Tuesday for January 2023 — Snort rules and prominent vulnerabilities
blogs_talos·2023-01-10·CVSS 8.1
CVE-2023-21743 [HIGH] Microsoft Patch Tuesday for January 2023 — Snort rules and prominent vulnerabilities
## Microsoft Patch Tuesday for January 2023 — Snort rules and prominent vulnerabilities
Microsoft released its monthly security update on Tuesday, disclosing 98 vulnerabilities. Of these vulnerabilities, 11 are classified as “Critical”, 87 are classified as “Important”, no vulnerability classified as “Moderate.”
According to Microsoft all “Critical“ vulnerability are either less likely or unlikely to be exploited, except of the security bypass vulnerability CVE-2023-21743 on Microsoft SharePoint Server machines. This vulnerability has a low complexity and can be easily triggered by an attacker. In a network-based attack, an unauthenticated user could make an anonymous connection to the targeted SharePoint server.
Two of the “Critical“ vulnerabilities, which Microsoft considers to be “le
Crowdstrike
January 2023 Patch Tuesday: Updates and Analysis
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How CrowdStrike is Accelerating Exposure Evaluation as Adversaries Gain Speed Apr 06, 2026
STARDUST CHOLLIMA Likely Compromises Axios npm Package Apr 01, 2026
Falcon for IT Supports Windows Secure Boot Certificate Lifecycle Management Apr 01, 2026
Detecting CVE-2026-20929: Kerberos Authentication Relay via CNAME Abuse Mar 31, 2026
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2023-01-10
Published