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CWE-786

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CWE-786

Access of Memory Location Before Start of Buffer

Base
Incomplete

Description

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

This typically occurs when a pointer or its index is decremented to a position before the buffer, when pointer arithmetic results in a position before the beginning of the valid memory location, or when a negative index is used.

Common Consequences

Scope

Confidentiality

Impact

Read Memory

Scope

Integrity
Availability

Impact

Modify Memory, DoS: Crash, Exit, or Restart

Scope

Integrity

Impact

Modify Memory, Execute Unauthorized Code or Commands

CVE-2002-2227

Unchecked length of SSLv2 challenge value leads to buffer underflow.

CVE-2007-4580

Buffer underflow from a small size value with a large buffer (length parameter inconsistency, CWE-130)

CVE-2007-1584

Buffer underflow from an all-whitespace string, which causes a counter to be decremented before the buffer while looking for a non-whitespace character.

CVE-2007-0886

Buffer underflow resultant from encoded data that triggers an integer overflow.

CVE-2006-6171

Product sets an incorrect buffer size limit, leading to "off-by-two" buffer underflow.

CVE-2006-4024

Negative value is used in a memcpy() operation, leading to buffer underflow.

CVE-2004-2620

Buffer underflow due to mishandled special characters

Applicable Platforms

Memory-Unsafe
C
C++

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