Szczegóły CWE-1389

The product parses numeric input assuming base 10 (decimal) values, but it does not account for inputs that use a different base number (radix).

Sposoby wprowadzenia

Implementation : Input validation used may assume decimal bases during conditional checks, when it may not always be the case.
Implementation : The application may rely on a service that supports different numerical bases.

Odpowiednie platformy

Język

Class: Not Language-Specific (Undetermined)

Technologie

Class: Not Technology-Specific (Undetermined)

Typowe konsekwencje

Zaobserwowane przykłady

Potencjalne środki zaradcze

Phases : Implementation
If only decimal-based values are expected in the application, conditional checks should be created in a way that prevent octal or hexadecimal strings from being checked. This can be achieved by converting any numerical string to an explicit base-10 integer prior to the conditional check, to prevent octal or hex values from ever being checked against the condition.
Phases : Implementation
If various numerical bases do need to be supported, check for leading values indicating the non-decimal base you wish to support (such as 0x for hex) and convert the numeric strings to integers of the respective base. Reject any other alternative-base string that is not intentionally supported by the application.
Phases : Implementation
If regular expressions are used to validate IP addresses, ensure that they are bounded using ^ and $ to prevent base-prepended IP addresses from being matched.

Metody wykrywania

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)

Uwagi dotyczące mapowania podatności

Uzasadnienie : This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Komentarz : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Odniesienia

REF-1284

Universal "netmask" npm package, used by 270,000+ projects, vulnerable to octal input data
Sick Codes.
https://sick.codes/universal-netmask-npm-package-used-by-270000-projects-vulnerable-to-octal-input-data-server-side-request-forgery-remote-file-inclusion-local-file-inclusion-and-more-cve-2021-28918/

Zgłoszenie

Modyfikacje