CVE-2021-26887
published 2021-03-11CVE-2021-26887: An elevation of privilege vulnerability exists in Microsoft Windows when Folder redirection has been enabled via Group Policy. When folder redirection file…
PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.92%
56.3th percentile
An elevation of privilege vulnerability exists in Microsoft Windows when Folder redirection has been enabled via Group Policy. When folder redirection file server is co-located with Terminal server, an attacker who successfully exploited the vulnerability would be able to begin redirecting another user's personal data to a created folder.
To exploit the vulnerability, an attacker can create a new folder under the Folder Redirection root path and create a junction on a newly created User folder. When the new user logs in, Folder Redirection would start redirecting to the folder and copying personal data.
This elevation of privilege vulnerability can only be addressed by reconfiguring Folder Redirection with Offline files and restricting permissions, and NOT via a security update for affected Windows Servers. See the FAQ section of this CVE for configuration guidance.
Affected
45 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_10 | — | — |
| microsoft | windows_10 | — | — |
| microsoft | windows_10 | — | — |
| microsoft | windows_10 | — | — |
| microsoft | windows_10 | — | — |
| microsoft | windows_10 | — | — |
| microsoft | windows_10_version_1507 | — | — |
| microsoft | windows_10_version_1607 | — | — |
| microsoft | windows_10_version_1803 | — | — |
| microsoft | windows_10_version_1809 | — | — |
| microsoft | windows_10_version_1909 | — | — |
| microsoft | windows_10_version_2004 | — | — |
| microsoft | windows_10_version_20h2 | — | — |
| microsoft | windows_7 | — | — |
| microsoft | windows_7_service_pack_1 | — | — |
| microsoft | windows_8.1 | — | — |
| microsoft | windows_server_2008 | — | — |
| microsoft | windows_server_2008_r2_service_pack_1 | — | — |
| microsoft | windows_server_2008_service_pack_2 | — | — |
| microsoft | windows_server_2012 | — | — |
| microsoft | windows_server_2012 | >= 6.2.0 < publication | publication |
| microsoft | windows_server_2012_r2 | — | — |
| microsoft | windows_server_2016 | — | — |
| microsoft | windows_server_2016 | — | — |
| microsoft | windows_server_2016 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
vendor_msrc7.8HIGH
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Microsoft
Microsoft Windows Folder Redirection Elevation of Privilege Vulnerability
vendor_msrc·2021-03-09·CVSS 7.8
CVE-2021-26887 [HIGH] Microsoft Windows Folder Redirection Elevation of Privilege Vulnerability
Microsoft Windows Folder Redirection Elevation of Privilege Vulnerability
Description: An elevation of privilege vulnerability exists in Microsoft Windows when Folder redirection has been enabled via Group Policy. When folder redirection file server is co-located with Terminal server, an attacker who successfully exploited the vulnerability would be able to begin redirecting another user's personal data to a created folder.
To exploit the vulnerability, an attacker can create a new folder under the Folder Redirection root path and create a junction on a newly created User folder. When the new user logs in, Folder Redirection would start redirecting to the folder and copying personal data.
This elevation of privilege vulnerability can only be addressed by reconfiguring Folder Redirection w
GHSA
GHSA-xphp-jrmh-9rjj: Microsoft Windows Folder Redirection Elevation of Privilege Vulnerability
ghsa_unreviewed·2022-05-24
CVE-2021-26887 [HIGH] CWE-269 GHSA-xphp-jrmh-9rjj: Microsoft Windows Folder Redirection Elevation of Privilege Vulnerability
Microsoft Windows Folder Redirection Elevation of Privilege Vulnerability
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-03-11
Published