CVE-2025-21355
CRITICALCVSS 9.8/10EPSS 1.50%
Last modified
CVE-2025-21355 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Missing Authentication for Critical Function in Microsoft Bing allows an unauthorized attacker to execute code over a network. EPSS estimates a 1.50% chance of exploitation in the next 30 days.
Description
Missing Authentication for Critical Function in Microsoft Bing allows an unauthorized attacker to execute code over a network
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Bing | All versions |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21355Patch, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2025-21355?
Missing Authentication for Critical Function in Microsoft Bing allows an unauthorized attacker to execute code over a network
How severe is CVE-2025-21355?
CVE-2025-21355 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.50% probability of exploitation in the next 30 days.
How do I fix CVE-2025-21355?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2025
- CVE-2025-21349Windows Remote Desktop Configuration Service Tampering Vulne…6.8
- CVE-2025-2135Type Confusion in V8 in Google Chrome prior to 134.0.6998.88…8.8
- CVE-2025-21350Windows Kerberos Denial of Service Vulnerability5.9
- CVE-2025-21351Windows Active Directory Domain Services API Denial of Servi…7.5
- CVE-2025-21352Internet Connection Sharing (ICS) Denial of Service Vulnerab…6.5
- CVE-2025-21354Microsoft Excel Remote Code Execution Vulnerability7.8
- CVE-2025-21356Microsoft Office Visio Remote Code Execution Vulnerability7.8
- CVE-2025-21357Microsoft Outlook Remote Code Execution Vulnerability6.7
- CVE-2025-21358Windows Core Messaging Elevation of Privileges Vulnerability7.8
- CVE-2025-21359Windows Kernel Security Feature Bypass Vulnerability7.8
- CVE-2025-2136Use after free in Inspector in Google Chrome prior to 134.0.…8.8
- CVE-2025-21360Microsoft AutoUpdate (MAU) Elevation of Privilege Vulnerabil…7.8
Are you affected by CVE-2025-21355?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST