What is CVE-2018-8527?

CVE-2018-8527 is a medium-severity vulnerability in Microsoft SQL Server Management Studio, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.5/10. Published 2018-10-10.

How severe is CVE-2018-8527?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Is CVE-2018-8527 known to be exploited?

4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XXE in Microsoft SQL Server Management Studio

CVE-2018-8527

An information disclosure vulnerability exists in Microsoft SQL Server Management Studio (SSMS) when parsing a malicious XEL file containing a reference to an external entity, aka "SQL Server Management Studio Information Disclosure Vulnerability." This affects SQL Server Management Studio 17.9, SQL Server Management Studio 18.0. This CVE ID is unique from CVE-2018-8532, CVE-2018-8533.

Vulnerability class: XXE (XML External Entity)

Published 2018-10-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.234 (97.7th percentile), scored 2026-10-01.

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 98th percentile — 97.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.234 · newest: 0.234 · change: 0.000

Affected products

Microsoft SQL Server Management Studio — versions 17.9, 18.0
Microsoft SQL Server Management Studio 17.9 — versions SQL Server Management Studio 17.9
Microsoft SQL Server Management Studio 18.0 — versions (Preview 4)

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

Public proof-of-concept exploits

References

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8527 (Patch, Vendor Advisory)
www.securityfocus.com/bid/105474 (VDB Entry, Third Party Advisory, vdb-entry)
www.securitytracker.com/id/1041826 (VDB Entry, Third Party Advisory, vdb-entry)
www.exploit-db.com/exploits/45585/ (Exploit, VDB Entry, Third Party Advisory, exploit)

Frequently asked questions

What is CVE-2018-8527?: CVE-2018-8527 is a medium-severity vulnerability in Microsoft SQL Server Management Studio, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 5.5/10. Published 2018-10-10.
How severe is CVE-2018-8527?: Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2018-8527 known to be exploited?: 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.