CVE-2018-8420
Status: ModifiedHigh (8.8)—💥 PoC
A remote code execution vulnerability exists when the Microsoft XML Core Services MSXML parser processes user input, aka "MS XML Remote Code Execution Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.
CVSS
- Version: 3.0
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Base score: 8.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 49%
- Percentile among all scored CVEs: 99
- Score date: 10/9/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
💥 Public exploits
Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.
- Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub
⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.
Affected technologies (4)
CWEs
- CWE-611
References
- http://www.securityfocus.com/bid/105259
- http://www.securitytracker.com/id/1041627
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8420
- http://www.securityfocus.com/bid/105259
- http://www.securitytracker.com/id/1041627
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8420
Raw JSON (NVD)
Show
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