CVE-2019-1171 — SymCrypt Information Disclosure Vulnerability

Executive Summary

An information disclosure vulnerability exists in SymCrypt during the OAEP decryption stage. An attacker who successfully exploited this vulnerability could obtain information to further compromise the user’s system. To exploit this vulnerability, an attacker would have to log on to an affected system and run a specially crafted application. The vulnerability would not allow an attacker to execute code or to elevate user rights directly, but it could be used to obtain information that could be used to try to further compromise the affected system. The update addresses the vulnerability through a software change to the OAEP decoding operations.

Overview

5.6

CVSS MEDIUM

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Information Disclosure

Released Aug 13 2019

Last Updated Aug 13 2019

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01371 — 0.68364 percentile

CVSS Vector

ATTACK VECTOR

Local

ATTACK COMPLEXITY

High

PRIVILEGES REQUIRED

Low

USER INTERACTION

None

SCOPE

Changed

Temporal Score: 5.1

EPSS Score

0.01371

probability of exploitation in the next 30 days

0.68364 percentile - updated 2026-06-20

View on FIRST.org

Affected Products

18 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 Version 1703 for 32-bit Systems	`4512507 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1703 for x64-based Systems	`4512507 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1709 for 32-bit Systems	`4512516 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1709 for ARM64-based Systems	`4512516 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1709 for x64-based Systems	`4512516 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1803 for 32-bit Systems	`4512501 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1803 for ARM64-based Systems	`4512501 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1803 for x64-based Systems	`4512501 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1809 for 32-bit Systems	`4511553 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1809 for ARM64-based Systems	`4511553 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1809 for x64-based Systems	`4511553 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1903 for 32-bit Systems	`4512508 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1903 for ARM64-based Systems	`4512508 (Security Update)`	Important	Information Disclosure	Yes
Windows 10 Version 1903 for x64-based Systems	`4512508 (Security Update)`	Important	Information Disclosure	Yes
Windows Server 2019	`4511553 (Security Update)`	Important	Information Disclosure	Yes
Windows Server 2019 (Server Core installation)	`4511553 (Security Update)`	Important	Information Disclosure	Yes
Windows Server, version 1803 (Server Core Installation)	`4512501 (Security Update)`	Important	Information Disclosure	Yes
Windows Server, version 1903 (Server Core installation)	`4512508 (Security Update)`	Important	Information Disclosure	Yes

Patches

5 patches

Article	Type	Restart
`4512507`	Security Update	Yes
`4512516`	Security Update	Yes
`4512501`	Security Update	Yes
`4511553`	Security Update	Yes
`4512508`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Jack Lloyd

References

MSRC Advisory MITRE NVD