Access of Memory Location After End of Buffer

Opis

The product reads or writes to a buffer using an index or pointer that references a memory location after the end of the buffer.

This typically occurs when a pointer or its index is incremented to a position after the buffer; or when pointer arithmetic results in a position after the buffer.

Skutki

• Confidentiality

  Read Memory

  For an out-of-bounds read, the attacker may have access to sensitive information. If the sensitive information contains system details, such as the current buffer's position in memory, this knowledge can be used to craft further attacks, possibly with more severe consequences.

• Integrity, Availability

  Modify Memory; DoS: Crash, Exit, or Restart

  Out of bounds memory access will very likely result in the corruption of relevant memory, and perhaps instructions, possibly leading to a crash. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

• Integrity

  Modify Memory; Execute Unauthorized Code or Commands

  If the memory accessible by the attacker can be effectively controlled, it may be possible to execute arbitrary code, as with a standard buffer overflow. If the attacker can overwrite a pointer's worth of memory (usually 32 or 64 bits), they can redirect a function pointer to their own malicious code. Even when the attacker can only modify a single byte arbitrary code execution can be possible. Sometimes this is because the same problem can be exploited repeatedly to the same effect. Other times it is because the attacker can overwrite security-critical application-specific data -- such as a flag indicating whether the user is an administrator.

Przykłady podatności

• CVE-2009-2550 Classic stack-based buffer overflow in media player using a long entry in a playlist
• CVE-2009-2403 Heap-based buffer overflow in media player using a long entry in a playlist
• CVE-2009-0689 large precision value in a format string triggers overflow
• CVE-2009-0558 attacker-controlled array index leads to code execution
• CVE-2008-4113 OS kernel trusts userland-supplied length value, allowing reading of sensitive information
• CVE-2007-4268 Chain: integer signedness error (CWE-195) passes signed comparison, leading to heap overflow (CWE-122)

Słabość nadrzędna

• CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

Słabości podrzędne

• CWE-121 Stack-based Buffer Overflow
• CWE-122 Heap-based Buffer Overflow
• CWE-126 Buffer Over-read

Kiedy powstaje

• Implementation

Dotyczy

Memory-Unsafe, C, C++

Źródła

1. Automated Source Code Reliability Measure (ASCRM) — Object Management Group (OMG), ASCRM-CWE-788, 2016
2. AddressSanitizer