CWE-789 Details

The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.

Einführungsmodi

Implementation

Anwendbare Plattformen

Sprache

Name: C (Undetermined)
Name: C++ (Undetermined)
Class: Not Language-Specific (Undetermined)

Häufige Konsequenzen

Beobachtete Beispiele

Mögliche Gegenmaßnahmen

Phases : Implementation // Architecture and Design
Perform adequate input validation against any value that influences the amount of memory that is allocated. Define an appropriate strategy for handling requests that exceed the limit, and consider supporting a configuration option so that the administrator can extend the amount of memory to be used if necessary.
Phases : Operation
Run your program using system-provided resource limits for memory. This might still cause the program to crash or exit, but the impact to the rest of the system will be minimized.

Erkennungsmethoden

Fuzzing

Fuzz testing (fuzzing) is a powerful technique for generating large numbers of diverse inputs - either randomly or algorithmically - and dynamically invoking the code with those inputs. Even with random inputs, it is often capable of generating unexpected results such as crashes, memory corruption, or resource consumption. Fuzzing effectively produces repeatable test cases that clearly indicate bugs, which helps developers to diagnose the issues.
Wirksamkeit : High

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.)
Wirksamkeit : High

Automated Dynamic Analysis

Use tools that are integrated during compilation to insert runtime error-checking mechanisms related to memory safety errors, such as AddressSanitizer (ASan) for C/C++ [REF-1518].
Wirksamkeit : Moderate

Hinweise zur Schwachstellen-Zuordnung

Begründung : This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Kommentar : 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.

Hinweise

This weakness can be closely associated with integer overflows (CWE-190). Integer overflow attacks would concentrate on providing an extremely large number that triggers an overflow that causes less memory to be allocated than expected. By providing a large value that does not trigger an integer overflow, the attacker could still cause excessive amounts of memory to be allocated.

Referenzen

REF-62

The Art of Software Security Assessment
Mark Dowd, John McDonald, Justin Schuh.

REF-962

Automated Source Code Security Measure (ASCSM)
Object Management Group (OMG).
http://www.omg.org/spec/ASCSM/1.0/

REF-1518

AddressSanitizer
https://clang.llvm.org/docs/AddressSanitizer.html

Einreichung

Änderungen