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CWE-125

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CWE-125

Out-of-bounds Read

Base
Draft

Description

The product reads data past the end, or before the beginning, of the intended buffer.

Common Consequences

Scope

Confidentiality

Impact

Read Memory

Scope

Confidentiality

Impact

Bypass Protection Mechanism

Scope

Availability

Impact

DoS: Crash, Exit, or Restart

Scope

Other

Impact

Varies by Context

Potential Mitigations

Implementation

Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright. To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

Architecture and Design

Use a language that provides appropriate memory abstractions.

CVE-2023-1018

The reference implementation code for a Trusted Platform Module does not implement length checks on data, allowing for an attacker to read 2 bytes past the end of a buffer.

CVE-2020-11899

Out-of-bounds read in IP stack used in embedded systems, as exploited in the wild per CISA KEV.

CVE-2014-0160

Chain: "Heartbleed" bug receives an inconsistent length parameter (CWE-130) enabling an out-of-bounds read (CWE-126), returning memory that could include private cryptographic keys and other sensitive data.

CVE-2021-40985

HTML conversion package has a buffer under-read, allowing a crash

CVE-2018-10887

Chain: unexpected sign extension (CWE-194) leads to integer overflow (CWE-190), causing an out-of-bounds read (CWE-125)

CVE-2009-2523

Chain: product does not handle when an input string is not NULL terminated (CWE-170), leading to buffer over-read (CWE-125) or heap-based buffer overflow (CWE-122).

CVE-2018-16069

Chain: series of floating-point precision errors (CWE-1339) in a web browser rendering engine causes out-of-bounds read (CWE-125), giving access to cross-origin data

CVE-2004-0112

out-of-bounds read due to improper length check

CVE-2004-0183

packet with large number of specified elements cause out-of-bounds read.

CVE-2004-0221

packet with large number of specified elements cause out-of-bounds read.

+4 more examples

Applicable Platforms

Memory-Unsafe
C
C++

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