An elevation of privilege vulnerability exists in rpcss.dll when the RPC service Activation Kernel improperly handles an RPC request.

published 2019-07-15 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-9670

cvss: 7.8; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 4.9%; EPSS 4.9% chance of exploitation in 30 days, percentile 92%
public exploits: 1; Exploit-DB

An elevation of privilege vulnerability exists in rpcss.dll when the RPC service Activation Kernel improperly handles an RPC request. To exploit this vulnerability, a low level authenticated attacker could run a specially crafted application. The security update addresses this vulnerability by correcting how rpcss.dll handles these requests., aka 'Windows RPCSS Elevation of Privilege Vulnerability'.

Patch / fix

links 1

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1089 advisory

Timeline

2019-07-15 Published
2019-07-18 First public exploit (EDB-47135)

Exploit prediction

4.91% chance of exploitation in the next 30 days, higher than 92% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

EDB-47135 Microsoft Windows 10 1903/1809 - RPCSS Activation Kernel Security Callback Privilege Escalation local, 2019-07-18

CVSS scores

assigned by	version	score	vector
NVD	3.0	7.8	CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

Microsoft Multiple

References

portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2019-1089
patch, vendor-advisory
packetstormsecurity.com /files/153683/Microsoft-Windows-RPCSS-Activation-Kernel-Security-Callback-Privilege-Escalation.html
third-party-advisory

Sources

CVE List CVE-2019-1089
NVD CVE-2019-1089

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Summary