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CVE-2018-25082: Wechat Sdk Python Project: XML external entity injection

CVE-2018-25082 is rated critical with a CVSS v3.1 base score of 9.8 and affects Wechat Sdk Python Project. 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

A vulnerability was found in zwczou WeChat SDK Python 0.3.0 and classified as critical. This issue affects the function validate/to_xml. The manipulation leads to xml external entity reference. The attack may be initiated remotely. Upgrading to version 0.5.5 is able to address this issue. The patch is named e54abadc777715b6dcb545c13214d1dea63df6c9. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-223403.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/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-611: Improper Restriction of XML External Entity Reference

The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

Affected products

Wechat Sdk Python Project: before 0.5.5