Weakness (CWE)
CWE-120: Buffer Copy without Checking Size of Input
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
How to prevent it (8 mitigations)
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Requirements
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer.
Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
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Architecture and Design
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Examples include the Safe C String Library (SafeStr) by Messier and Viega [REF-57], and the Strsafe.h library from Microsoft [REF-56]. These libraries provide safer versions of overflow-prone string-handling functions.
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Operation, Build and Compilation
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
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Implementation
Consider adhering to the following rules when allocating and managing an application's memory:
- Double check that your buffer is as large as you specify.
- When using functions that accept a number of bytes to copy, such as strncpy(), be aware that if the destination buffer size is equal to the source buffer size, it may not NULL-terminate the string.
- Check buffer boundaries if accessing the buffer in a loop and make sure there is no danger of writing past the allocated space.
- If necessary, truncate all input strings to a reasonable length before passing them to the copy and concatenation functions.
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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.
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Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
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Operation, Build and Compilation
Run or compile the software using features or extensions that randomly arrange the positions of a program's executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as "rebasing" (for Windows) and "prelinking" (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].
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Operation
Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX [REF-60] [REF-61]. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment.
For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND [REF-1336].
Source: MITRE CWE-120
3,302 results · Feed
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender component
Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics component
Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Firefox ESR 115.41, Firefox ESR 140.16, and Thunderbird 140.16.
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
-
High 8.8
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.…
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High 8.4
A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Sequo…
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Medium 5.5
A buffer overflow was addressed with improved bounds checking. This issue is fixed in iOS 18.7.10 and iPadOS 18.7.10, i…
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High 8.8
A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Sequo…
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High 7.8
An out-of-bounds access issue was addressed with improved bounds checking. This issue is fixed in iOS 27 and iPadOS 27,…
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High 7.8
The issue was addressed with improved memory handling. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.…
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Medium 4.3
A buffer overflow was addressed with improved bounds checking. This issue is fixed in iOS 27 and iPadOS 27, macOS Golde…
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High 7.8
A buffer overflow was addressed with improved size validation. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 …
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High 8.2
An access issue was addressed with additional sandbox restrictions. This issue is fixed in macOS Golden Gate 27, macOS …
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Critical 9.8
A permissions issue was addressed with improved path validation. This issue is fixed in iOS 27 and iPadOS 27, macOS Gol…
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Critical 9.8CVE-2026-84520 Public exploit
A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Golden Gate 27. A local att…
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Medium 6.5
A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Sequo…
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High 7.3
The issue was addressed with improved memory handling. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPad…
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Critical 9.8
resdata insufficiently validates untrusted GRDECL files
resdata is software for reading and writing result files from the Eclipse reservoir simulator. Prior to 6.2.9, resdata insufficiently validates numeric fields, grid dimensions, keyword sizes, and array indexes while parsing untrusted GRDECL files in lib/resda…
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Medium 4.8
GNU Binutils Eh Frame Section elf-eh-frame.c _bfd_elf_write_section_eh_frame buffer overflow
A vulnerability was detected in GNU Binutils 2.47. Affected by this issue is the function _bfd_elf_write_section_eh_frame of the file bfd/elf-eh-frame.c of the component Eh Frame Section Handler. Performing a manipulation of the argument cie_length/fde_length…
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Medium 5.3
GNU Binutils ld elf64-x86-64.c elf_x86_64_relocate_section buffer overflow
A security vulnerability has been detected in GNU Binutils 2.47. Affected by this vulnerability is the function elf_x86_64_relocate_section of the file bfd/elf64-x86-64.c of the component ld. Such manipulation of the argument roff leads to buffer overflow. An…
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Medium 5.3
GNU Binutils ld cache.c cache_bwrite buffer overflow
A security flaw has been discovered in GNU Binutils 2.47. This impacts the function cache_bwrite of the file bfd/cache.c of the component ld. The manipulation of the argument nbytes results in buffer overflow. The attack requires a local approach. The exploit…
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High 8.8
Buffer overflow vulnerability exists in Contec EC1000 series. If a remote attacker sends a specially crafted request to…
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High 8.8
Buffer overflow vulnerability exists in Contec RP-WAH-SR Series. If a remote attacker sends a specially crafted request…
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Medium 6.8
Buffer overflow vulnerability in Panasonic Industry USB Driver for MINAS A5/A6 allows attackers to stop Windows.
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Critical 9.9
Totolink A3002MU boa formPortFw buffer overflow
A flaw has been found in Totolink A3002MU Hh-B20211125.1046. The affected element is the function formPortFw of the file /boafrm/formPortFw of the component boa. This manipulation of the argument service_type causes buffer overflow. It is possible to initiate…
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Critical 9.9
Totolink A3002MU boa formNewSchedule buffer overflow
A vulnerability was detected in Totolink A3002MU Hh-B20211125.1046. Impacted is the function formNewSchedule of the file /boafrm/formNewSchedule of the component boa. The manipulation of the argument submit-url results in buffer overflow. The attack may be pe…
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Low 2.9
Portable Puzzle Collection before 20230116.5782e29 was discovered to contain a buffer overflow which allows attackers t…
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Low 2.9
Portable Puzzle Collection before 20230116.5782e29 was discovered to contain a buffer overflow via the "M" command.
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Low 2.9
Portable Puzzle Collection before 20230116.5782e29 was discovered to contain a buffer overflow via the record length pa…
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Low 2.9
Portable Puzzle Collection before 20230116.5782e29 was discovered to contain a buffer overflow via the game description…
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Low 2.9
Portable Puzzle Collection before 20230116.5782e29 was discovered to contain a buffer overflow which is triggered when …
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Low 2.9
Portable Puzzle Collection before 20230116.5782e29 was discovered to contain a buffer overflow via the is_markable() fu…
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Critical 9.9
Totolink A3002MU boa formIpv6Setup buffer overflow
A security vulnerability has been detected in Totolink A3002MU Hh-B20211125.1046. This issue affects the function formIpv6Setup of the file /boafrm/formIpv6Setup of the component boa. The manipulation of the argument static_ipv6 leads to buffer overflow. The …
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Critical 9.9
Totolink A3002MU boa formFilter buffer overflow
A weakness has been identified in Totolink A3002MU Hh-B20211125.1046. This vulnerability affects the function formFilter of the file /boafrm/formFilter of the component boa. Executing a manipulation of the argument ip6addr can lead to buffer overflow. The att…
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High 7.5
SIPp through 3.7.7 Buffer Overflow via Oversized SIP Header Content
SIPp through 3.7.7 contains a buffer overflow vulnerability in the get_header() function in src/sip_parser.cpp when processing SIP messages with header content exceeding 20,490 bytes. Unauthenticated remote attackers can send crafted SIP messages with oversiz…