MSRC_CVE-2026-26154
Vulnerability from csaf_microsoft - Published: 2026-04-14 07:00 - Updated: 2026-04-14 07:00Summary
Windows Server Update Service (WSUS) Tampering Vulnerability
Severity
Important
Notes
Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Customer Action: Required. The vulnerability documented by this CVE requires customer action to resolve.
CWE-20
- Improper Input Validation
Vendor Fix
10.0.17763.8644:Security Update:https://support.microsoft.com/help/5082123
https://support.microsoft.com/help/5082123
Vendor Fix
10.0.20348.5020:Security Update:https://support.microsoft.com/help/5082142
https://support.microsoft.com/help/5082142
Vendor Fix
10.0.26100.32690:Security Update:https://support.microsoft.com/help/5082063
https://support.microsoft.com/help/5082063
Vendor Fix
10.0.25398.2274:Security Update:https://support.microsoft.com/help/5082060
https://support.microsoft.com/help/5082060
Vendor Fix
10.0.14393.9060:Security Update:https://support.microsoft.com/help/5082198
https://support.microsoft.com/help/5082198
Vendor Fix
6.2.9200.26026:Monthly Rollup:https://support.microsoft.com/help/5082127
https://support.microsoft.com/help/5082127
Vendor Fix
6.3.9600.23132:Monthly Rollup:https://support.microsoft.com/help/5082126
https://support.microsoft.com/help/5082126
References
Acknowledgments
f7d8c52bec79e42795cf15888b85cbad
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"title": "Assigning CNA"
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"scores": [
{
"cvss_v3": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"environmentalsScore": 0.0,
"exploitCodeMaturity": "UNPROVEN",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"remediationLevel": "OFFICIAL_FIX",
"reportConfidence": "CONFIRMED",
"scope": "UNCHANGED",
"temporalScore": 6.5,
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C",
"version": "3.1"
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"threats": [
{
"category": "impact",
"details": "Tampering"
},
{
"category": "exploit_status",
"details": "Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely"
}
],
"title": "Windows Server Update Service (WSUS) Tampering Vulnerability"
}
]
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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