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CVE-2016-4991: Nodepdf Project: Improper Neutralization of Special Elements used in a Command
CVE-2016-4991 is rated critical with a CVSS v3.1 base score of 9.8 and affects Nodepdf 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
Input passed to the Pdf() function is shell escaped and passed to child_process.exec() during PDF rendering. However, the shell escape does not properly encode all special characters, namely, semicolon and curly braces. This can be abused to achieve command execution. This problem affects nodepdf 1.3.0.
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-77: Improper Neutralization of Special Elements used in a Command
The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
Affected products
- Nodepdf Project: 1.3.0