CVE-2018-8420: A remote code execution vulnerability exists when the Microsoft XML Core Services MSXML parser processes user input, aka "MS XML Remote Code…
Noroxi assessment
Priority: Plan (action score 50/100)
- Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
- Probability of exploitation in the next 30 days: 48.9% (FIRST EPSS); higher than 98.8% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
- According to the record, no fixed version is available yet.
Add it to your regular patch cycle. Update when a fix is released; follow the vendor's advisory.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
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.
- Published
- Sep 12, 2018
- Updated
- Jun 16, 2026
- EPSS
- 48.9% · 98th percentile
- CWE
- CWE-611
Report tools
Action score
50
Add it to your regular patch cycle.
- CVSS
- 35 / 40 · 8.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 15 / 30 · 48.9%
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- Proof of concept exists, no weaponized module
- No fixed version yet
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| microsoft | windows 10 | cpe:2.3:o:microsoft:windows_10 |
| microsoft | windows 7 | cpe:2.3:o:microsoft:windows_7 |
| microsoft | windows 8.1 | cpe:2.3:o:microsoft:windows_8.1 |
| microsoft | windows server | cpe:2.3:o:microsoft:windows_server |
Versions reported by the vendor
Affected version ranges reported by the assigning authority (microsoft). Independent of NVD's CPE analysis and usually ahead of it.
Microsoft Windows 10
- 32-bit Systems, Version 1607 for 32-bit Systems, Version 1607 for x64-based Systems, Version 1703 for 32-bit Systems, Version 1703 for x64-based Systems, Version 1709 for 32-bit Systems, Version 1709 for x64-based Systems, Version 1803 for 32-bit Systems, Version 1803 for x64-based Systems, x64-based Systemsaffected
Microsoft Windows 10 Servers
- version 1709 (Server Core Installation), version 1803 (Server Core Installation)affected
Microsoft Windows 7
- 32-bit Systems Service Pack 1, x64-based Systems Service Pack 1affected
Microsoft Windows 8.1
- 32-bit systems, x64-based systemsaffected
Microsoft Windows RT 8.1
- Windows RT 8.1affected
Microsoft Windows Server 2008
- 32-bit Systems Service Pack 2, 32-bit Systems Service Pack 2 (Server Core installation), Itanium-Based Systems Service Pack 2, x64-based Systems Service Pack 2, x64-based Systems Service Pack 2 (Server Core installation)affected
Microsoft Windows Server 2008 R2
- Itanium-Based Systems Service Pack 1, x64-based Systems Service Pack 1, x64-based Systems Service Pack 1 (Server Core installation)affected
Microsoft Windows Server 2012
- (Server Core installation)affected
Microsoft Windows Server 2012 R2
- (Server Core installation)affected
Microsoft Windows Server 2016
- (Server Core installation)affected
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- microsoft windows server2008
- microsoft windows server2012
- microsoft windows server2016
Same product
microsoft: all recordsOther highest-scoring records for the same primary product.
- CVE-2015-2426Buffer underflow in atmfd.dll in the Windows Adobe Type Manager Library in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1…KEV91Now
- CVE-2022-21907HTTP Protocol Stack Remote Code Execution Vulnerability67This week
- CVE-2022-26809Remote Procedure Call Runtime Remote Code Execution Vulnerability66This week
Published before and after this one in the same product
- ← EarlierCVE-2018-8410Sep 12, 2018 · An elevation of privilege vulnerability exists when the Windows Kernel API improperly handles registry objects in memory, aka "Windows…32Monitor
- ← EarlierCVE-2018-8419Sep 12, 2018 · An information disclosure vulnerability exists when the Windows kernel fails to properly initialize a memory address, aka "Windows Kernel…23Monitor
- Later →CVE-2018-8424Sep 12, 2018 · An information disclosure vulnerability exists when the Windows GDI component improperly discloses the contents of its memory, aka "Windows…30Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Proof-of-concept repository on GitHub ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Proof-of-concept repository on GitHub | stars:1 | 2018-09-12 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- First PoC-1 d
- Published
- TodayNov 15, 2026+2986 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Not on record for this CVE: patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-611 · Improper Restriction of XML External Entity ReferenceCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
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Change log (0)
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Show all references (2 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.