Multiple vulnerabilities in Microsoft products (August 21, 2026)
Multiple vulnerabilities have been discovered in Microsoft products. They allow an attacker to cause a security policy bypass and denial of service.
CSIRTS triage
- What
- Multiple vulnerabilities in Microsoft products allow security policy bypass and denial of service.
- Who is affected
- Deployments of affected Microsoft products running vulnerable versions.
- Urgency
- Multiple attack vectors present; remediation urgency depends on specific product exposure and patch availability.
- Action
- Identify which Microsoft products are affected by CVE-2026-55015 and CVE-2026-55013 and apply patches as released.
AI-assisted analysis generated from the source advisory — verify against the original.
Details
Original advisory: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1073/
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-550150.50% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 41% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-550130.23% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 14% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-55015 | coverage & exploitation status | NVD · CVE.org |
| CVE-2026-55013 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- medium[NEW] [medium] Microsoft Windows Services: Multiple Vulnerabilitiescert-bund
- mediumCVE-2026-55015: Uncontrolled search path element in Windows Remote Help allows an authorized attacker to deny …nvd
- highCVE-2026-55013: Uncontrolled search path element in Windows Remote Help Defense allows an authorized attacker …nvd
- highCVE-2026-55013: Windows Remote Help Defense Spoofing Vulnerabilitymsrc
- mediumCVE-2026-55015: Microsoft Remote Help Denial of Service Vulnerabilitymsrc
Recent advisories for Microsoft products
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- high[NEW] [high] Microsoft Office Products: Multiple Vulnerabilitiescert-bund · 2026-08-21
- highCVE-2026-60998: Vulnerability in the Oracle Identity Manager Connector product of Oracle Fusion Middleware (co…nvd · 2026-08-18
- critical[NEW] [critical] Microsoft Windows products: Multiple vulnerabilitiescert-bund · 2026-08-18
- unknownMultiple vulnerabilities in Microsoft products (August 17, 2026)cert-fr-avis · 2026-08-17
- critical[NEW] [critical] Microsoft Windows Products: Multiple vulnerabilitiescert-bund · 2026-08-14
- critical[NEW] [critical] Microsoft Office products: Multiple vulnerabilitiescert-bund · 2026-08-13
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