Information disclosure vulnerabilities in Nextcloud Server
| Risk | Low |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2018-3761 CVE-2018-3762 |
| CWE-ID | CWE-20 CWE-273 |
| 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 2 vulnerabilities.
1) Improper input validation
EUVDB-ID: #VU14214
Risk: Low
CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2018-3761
CWE-ID:
CWE-20 - Improper input validation
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to obtain potentially sensitive information on the target system.
The vulnerability exists due to insufficient input validation. A remote attacker with access to the OAuth2 refresh token can trick the victim into opening a specially crafted data and obtain new tokens.
MitigationUpdate to version 12.0.8 or 13.0.3.
Vulnerable software versionsNextcloud Server: 12.0.0 - 13.0.2
External linkshttp://nextcloud.com/security/advisory/?id=nc-sa-2018-003
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker 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: #VU14215
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-2018-3762
CWE-ID:
CWE-273 - Improper Check for Dropped Privileges
Exploit availability: No
DescriptionThe vulnerability allows a remote authenticated attacker to obtain potentially sensitive information on the target system.
The vulnerability exists due to a missing check for read permissions. A remote attacker who receive an incomming share containing files tagged can still request a preview for arbitrary files.
MitigationUpdate to version 12.0.8 or 13.0.3.
Vulnerable software versionsNextcloud Server: 12.0.0 - 13.0.2
External linkshttp://nextcloud.com/security/advisory/?id=nc-sa-2018-002
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.
