Quantum Secular Labs / Blog / Advisories
CVE-2018-20718: Pydio: Deserialization of Untrusted Data
CVE-2018-20718 is rated critical with a CVSS v3.0 base score of 9.8 and affects Pydio. 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
In Pydio before 8.2.2, an attack is possible via PHP Object Injection because a user is allowed to use the $phpserial$a:0:{} syntax to store a preference. An attacker either needs a "public link" of a file, or access to any unprivileged user account for creation of such a link.
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-502: Deserialization of Untrusted Data
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Affected products
- Pydio: before 8.2.2