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 8.1
Coturn: Stack buffer overflow in decode_oauth_token_gcm()
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High 7.5
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High 8.8
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Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in RTI Connext Professional (Web Integration Service) allows Filter Failure through Buffer Overflow. This issue affects Connext Professional: from 7.4.0 before 7.7.0.1, from …
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High 8.4CVE-2025-26240 Public exploit
pdfkit: Path traversal in from_string
In JazzCore python-pdfkit 1.0.0, the from_string method enables the execution of JavaScript code within the context of the server application and the exfiltration of local files.
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Medium 6.5
In several functions of the RTCP packet decoder, there is a possible out-of-bounds read due to a missing bounds check. …
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High 8.8
In Modem, there is a possible out of bounds write due to a missing bounds check. This could lead to remote code executi…
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High 8.8
In TextRtpPayloadDecoderNode::DecodeT140 of TextRtpPayloadDecoderNode.cpp, there is a possible out of bounds write due …
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Medium 4.3
In RtcpHeader::decodeRtcpHeader, there is a possible OOB read due to a missing bounds check. This could lead to remote …
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Medium 5.3
In ImsMediaBitReader::ReadByteBuffer, there is a possible OOB read due to a missing bounds check. This could lead to re…
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High 8.8
In Modem, there is a possible way to trigger a modem crash during a SIP REFER request due to memory corruption. This co…
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High 8.8
In __mfc_core_nal_q_get_dec_metadata_sei_nal of mfc_core_nal_q.c, there is a possible out of bounds write due to a miss…
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High 8.8
In mfc_core_get_dec_metadata_sei_nal of mfc_core_reg_api.c, there is a possible out of bounds write due to a missing bo…
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High 7.5
In writeAocCommand of AocAudioCodec.cpp, there is a possible memory safety issue due to a missing bounds check. This co…
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Medium 5.3
In decodeAppPacket of RtcpAppPacket.cpp, there is a possible OOB read due to a missing bounds check. This could lead to…
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High 7.8
In lwis_io_buffer_write of lwis_io_buffer.c, there is a possible out of bounds write due to memory corruption. This cou…
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High 7.5
In Modem, there is a possible out of bounds read due to a missing bounds check. This could lead to remote denial of ser…
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Medium 4.3
In RtcpByePacket::decodeByePacket, there is a possible due to a missing bounds check. This could lead to remote informa…
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High 8.8
In WC-Radio, there is a possible out of bounds write due to a missing bounds check. This could lead to remote code exec…
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High 8.1
Memory safety bugs fixed in Firefox ESR 115.37, Firefox ESR 140.12, Thunderbird ESR 140.12, Firefox 152 and Thunderbird 152
Memory safety bugs present in Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploit…
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High 8.8
GALAYOU Y4 Web Server buffer overflow
A vulnerability was determined in GALAYOU Y4 1.0.0. Impacted is an unknown function of the component Web Server. This manipulation causes buffer overflow. The attack is only possible within the local network. The exploit has been publicly disclosed and may be…
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High 8.8
Stack buffer overflow in SCTP error cause parsing in inet_drv allows remote VM crash
Stack-based Buffer Overflow vulnerability in Erlang OTP erts (inet_drv) allows an unauthenticated remote attacker to crash the BEAM VM by sending a crafted SCTP ERROR chunk. The sctp_parse_error_chunk function in erts/emulator/drivers/common/inet_drv.c parses…
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High 7.5
DBI versions before 1.648 for Perl saved errors in a limited-sized buffer
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda G0 v15.11.0.5 was discovered to contain a stack overflow in the picCropName pa…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the gotoUrl pa…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the webAuthWhi…
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High 7.5
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High 7.5
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda G0 v15.11.0.5 was discovered to contain a buffer overflow in the IPMacBindRule…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda G0 v15.11.0.5 was discovered to contain a buffer overflow in the portalAuth pa…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda G0 v15.11.0.5 was discovered to contain a buffer overflow in the IPMacBindInde…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the picName pa…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda G0 v15.11.0.5 was discovered to contain a stack overflow in the IPMacBindRuleI…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda PW201A v1.0.5 was discovered to contain a buffer overflow in the page paramete…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the webAuthWhi…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda PW201A v1.0.5 was discovered to contain a buffer overflow in the page paramete…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W20E v15.11.0.6 was discovered to contain a buffer overflow in the wewifiWhite…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the webAuthUse…
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High 7.5
Shenzhen Tenda Technology Co., Ltd Tenda W15E v15.11.0.10 was discovered to contain a buffer overflow in the webAuthUse…
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Critical 9.8
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High 7.5CVE-2026-42536 Public exploit
Apache HTTP Server: mod_xml2enc heap overflow
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