Multiple vulnerabilities in Nextcloud Server
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 3 |
| CVE-ID | CVE-2021-41233 CVE-2021-41239 CVE-2021-41241 |
| CWE-ID | CWE-200 CWE-285 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software Subscribe |
Nextcloud Server Client/Desktop applications / Messaging software |
| Vendor | Nextcloud |
Security Bulletin
This security bulletin contains information about 3 vulnerabilities.
1) Information disclosure
EUVDB-ID: #VU61274
Risk: Low
CVSSv3.1: 3.8 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-41233
CWE-ID:
CWE-200 - Information exposure
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in the Nextcloud Text application. A remote user can access the folder names of "File Drop".
MitigationInstall updates from vendor's website.
Vulnerable software versionsNextcloud Server: 20.0.0 - 22.2.0
External linkshttp://github.com/nextcloud/text/pull/1884
http://github.com/nextcloud/security-advisories/security/advisories/GHSA-26c8-35cm-xq9m
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Information disclosure
EUVDB-ID: #VU61277
Risk: Medium
CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-41239
CWE-ID:
CWE-200 - Information exposure
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to User Status API does not consider the user enumeration settings by the administrator. A remote user can gain unauthorized access to sensitive information on the system.
MitigationInstall updates from vendor's website.
Vulnerable software versionsNextcloud Server: 20.0.0 - 22.2.0
External linkshttp://github.com/nextcloud/security-advisories/security/advisories/GHSA-g722-cm3h-8wrx
http://github.com/nextcloud/server/pull/29260
http://github.com/nextcloud/server/issues/27122
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
3) Improper Authorization
EUVDB-ID: #VU61276
Risk: Medium
CVSSv3.1: 5.5 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-41241
CWE-ID:
CWE-285 - Improper Authorization
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to bypass authorization check.
The vulnerability exists due to insufficient authorization validation in the groupfolders application. A remote user can gain access to the groupfolder but not specific subfolders.
MitigationInstall updates from vendor's website.
Vulnerable software versionsNextcloud Server: 20.0.0 - 22.2.0
External linkshttp://github.com/nextcloud/security-advisories/security/advisories/GHSA-m4wp-r357-4q94
http://github.com/nextcloud/server/pull/29362
http://github.com/nextcloud/groupfolders/issues/1692
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
