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CVE-2017-15887: Synology Carddav Server: Improper Restriction of Excessive Authentication Attempts
CVE-2017-15887 is rated critical with a CVSS v3.0 base score of 9.8 and affects Synology Carddav Server. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.
Vulnerability description
An improper restriction of excessive authentication attempts vulnerability in /principals in Synology CardDAV Server before 6.0.7-0085 allows remote attackers to obtain user credentials via a brute-force attack.
Severity breakdown
CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Unchanged. Impact stays within the vulnerable component.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: High. Total loss of availability; the component can be shut down.
Underlying weakness
CWE-307: Improper Restriction of Excessive Authentication Attempts
The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.
Affected products
- Synology Carddav Server: before 6.0.7-0085