CWEweakness

CWE-126 Buffer Over-read

Official page ↗
Abstraction
Variant
Structure
Simple
Status
Draft
Languages
C, C++, Memory-Unsafe
CWE version
5.0

Description

The product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations after the targeted buffer.

Common consequences

• Confidentiality: Read Memory • Confidentiality: Bypass Protection Mechanism — By reading out-of-bounds memory, an attacker might be able to get secret values, such as memory addresses, which can bypass protection mechanisms such as ASLR in order to improve the reliability and likelihood of exploiting a separate weakness to achieve code execution instead of just denial of service. • Availability, Integrity: DoS: Crash, Exit, or Restart — An attacker might be able to cause a crash or other denial of service by causing the product to read a memory location that is not allowed (such as a segmentation fault), or to cause other conditions in which the read operation returns more data than is expected.

Detection methods

• 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.) • 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].

Observed examples

• CVE-2026-7320: Out-of-bounds read in audio processor used in a common web browser, allowing a read of the global data section • CVE-2022-1733: Text editor has out-of-bounds read past end of line while indenting C code • 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-2009-2523: Chain: product does not handle when an input string is not NULL terminated, leading to buffer over-read or heap-based buffer overflow.

Related

Observed example · CVE (4)

  • CVE-2026-7320 Information disclosure due to incorrect boundary conditions in the Audio/Video component. vulnerability
  • CVE-2022-1733 Heap-based Buffer Overflow in GitHub repository vim/vim prior to 8.2.4968. vulnerability
  • CVE-2014-0160 The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly handle Heartbeat Extension packets, which allows… vulnerability
  • CVE-2009-2523 The License Logging Server (llssrv.exe) in Microsoft Windows 2000 SP4 allows remote attackers to execute arbitrary code via an RPC message… vulnerability

Child of · CWE (2)

  • CWE-125 Out-of-bounds Read weakness
  • CWE-788 Access of Memory Location After End of Buffer weakness

Referenced by CVE · weakness (579)

  • CVE-2026-93524 A buffer overread in CheckKeySyms() in X.Org X Server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients… vulnerability
  • CVE-2026-57185 Asterisk is an open source private branch exchange and telephony toolkit. vulnerability
  • CVE-2026-53920 odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. vulnerability
  • CVE-2026-55606 odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. vulnerability
  • CVE-2026-112394 Pillow is a Python imaging library. vulnerability
  • CVE-2026-112404 Pillow is a Python imaging library. vulnerability
  • CVE-2026-46471 An issue was discovered in GStreamer gst-plugins-good before 1.28.2. vulnerability
  • CVE-2026-85745 MariaDB server is a community developed fork of MySQL server. vulnerability
  • CVE-2026-101310 The HDA audio device model did not check for zero-length Buffer Descriptor List (BDL) entries when starting a stream. vulnerability
  • CVE-2026-108454 Buffer over-read in Microsoft Office PowerPoint allows an unauthorized attacker to disclose information over a network. vulnerability
  • CVE-2026-103567 Buffer over-read in Windows Broadcast DVR User Service allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-69884 Buffer over-read in Windows GDI allows an authorized attacker to elevate privileges locally. vulnerability
  • CVE-2026-69942 Buffer over-read in Windows Overlay Filter allows an authorized attacker to execute code locally. vulnerability
  • CVE-2026-69950 Buffer over-read in Windows Overlay Filter allows an authorized attacker to elevate privileges locally. vulnerability
  • CVE-2026-69953 Buffer over-read in Windows Overlay Filter allows an authorized attacker to elevate privileges locally. vulnerability
  • CVE-2026-69954 Buffer over-read in Windows Overlay Filter allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-69957 Integer overflow or wraparound in Windows Overlay Filter allows an authorized attacker to elevate privileges locally. vulnerability
  • CVE-2026-70041 Buffer over-read in Windows CD-ROM Driver allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-70234 Buffer over-read in Desktop Window Manager allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-83565 Buffer over-read in Windows Encrypting File System (EFS) allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-83685 Buffer over-read in Windows IKE Extension allows an authorized attacker to deny service over a network. vulnerability
  • CVE-2026-83719 Buffer over-read in Servicing Stack Updates allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-83727 Buffer over-read in Windows Overlay Filter allows an authorized attacker to elevate privileges locally. vulnerability
  • CVE-2026-83788 Buffer over-read in Windows RNDIS allows an unauthorized attacker to disclose information with a physical attack. vulnerability
  • CVE-2026-83835 Buffer over-read in Windows Common Log File System Driver allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-83888 Buffer over-read in Windows CD-ROM Driver allows an unauthorized attacker to elevate privileges over a network. vulnerability
  • CVE-2026-85835 Buffer over-read in Servicing Stack Updates allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-85910 Buffer over-read in Windows StateRepository API allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-85935 Buffer over-read in Windows USB Driver allows an authorized attacker to disclose information locally. vulnerability
  • CVE-2026-88167 Buffer over-read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network. vulnerability
Show all 579 ›

Referenced by CWE · can precede (1)

  • CWE-170 Improper Null Termination weakness

Referenced by CWE · overlaps (1)

  • CWE-788 Access of Memory Location After End of Buffer weakness