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
3,303 results · Feed
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High 8.8
Tenda AC18 AdvSetLanip fromadvsetlanip buffer overflow
A vulnerability classified as critical was found in Tenda AC18 15.03.05.05. Affected by this vulnerability is the function fromadvsetlanip of the file /goform/AdvSetLanip. The manipulation of the argument lanMask leads to buffer overflow. The attack can be la…
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High 8.8
Tenda AC18 SetSysAutoRebbotCfg formsetreboottimer buffer overflow
A vulnerability classified as critical has been found in Tenda AC18 15.03.05.05. Affected is the function formsetreboottimer of the file /goform/SetSysAutoRebbotCfg. The manipulation of the argument rebootTime leads to buffer overflow. It is possible to launc…
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High 8.8
Tenda AC18 setPptpUserList formSetPPTPUserList buffer overflow
A vulnerability was found in Tenda AC18 15.03.05.05. It has been rated as critical. This issue affects the function formSetPPTPUserList of the file /goform/setPptpUserList. The manipulation of the argument list leads to buffer overflow. The attack may be init…
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High 7.3
FreeFloat FTP Server REGET Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0. It has been classified as critical. Affected is an unknown function of the component REGET Command Handler. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. The exp…
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High 7.3
FreeFloat FTP Server PROGRESS Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0 and classified as critical. This issue affects some unknown processing of the component PROGRESS Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. The exploi…
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High 7.3
FreeFloat FTP Server SET Command buffer overflow
A vulnerability has been found in FreeFloat FTP Server 1.0 and classified as critical. This vulnerability affects unknown code of the component SET Command Handler. The manipulation leads to buffer overflow. The attack can be initiated remotely. The exploit h…
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High 7.3
FreeFloat FTP Server HOST Command buffer overflow
A vulnerability, which was classified as critical, was found in FreeFloat FTP Server 1.0. This affects an unknown part of the component HOST Command Handler. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exploi…
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High 7.3
FreeFloat FTP Server PASSIVE Command buffer overflow
A vulnerability, which was classified as critical, has been found in FreeFloat FTP Server 1.0. Affected by this issue is some unknown functionality of the component PASSIVE Command Handler. The manipulation leads to buffer overflow. The attack may be launched…
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High 7.8
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in Wireshark
Column handling crashes in Wireshark 4.4.0 to 4.4.6 and 4.2.0 to 4.2.12 allows denial of service via packet injection or crafted capture file
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High 7.3
FreeFloat FTP Server SYSTEM Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0. It has been classified as critical. This affects an unknown part of the component SYSTEM Command Handler. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exp…
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High 7.3
FreeFloat FTP Server PBSZ Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0 and classified as critical. Affected by this issue is some unknown functionality of the component PBSZ Command Handler. The manipulation leads to buffer overflow. The attack may be launched remotely. The e…
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High 7.3
FreeFloat FTP Server PASV Command buffer overflow
A vulnerability has been found in FreeFloat FTP Server 1.0 and classified as critical. Affected by this vulnerability is an unknown functionality of the component PASV Command Handler. The manipulation leads to buffer overflow. The attack can be launched remo…
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High 7.3
FreeFloat FTP Server NOOP Command buffer overflow
A vulnerability, which was classified as critical, was found in FreeFloat FTP Server 1.0. Affected is an unknown function of the component NOOP Command Handler. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. The explo…
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High 7.3
FreeFloat FTP Server CDUP Command buffer overflow
A vulnerability, which was classified as critical, has been found in FreeFloat FTP Server 1.0. This issue affects some unknown processing of the component CDUP Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. T…
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Medium 6.6
Buffer Copy Without Checking Size of Input in Audio
Memory corruption may occur while processing voice call registration with user.
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Medium 5.1
In cplog service, there is a possible out of bounds write due to a missing bounds check. This could lead to local denia…
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Critical 9.8
A buffer overflow in the the Sangoma IMG2020 HTTP server through 2.3.9.6 allows an unauthenticated user to achieve remo…
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Critical 9.8
WAVLINK WL-WN576K1 HTTP POST Request login.cgi sys_login buffer overflow
A vulnerability was found in WAVLINK QUANTUM D2G, QUANTUM D3G, WL-WN530G3A, WL-WN530HG3, WL-WN532A3 and WL-WN576K1 up to V1410_240222 and classified as critical. Affected by this issue is the function sys_login of the file /cgi-bin/login.cgi of the component …
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High 7.3
FreeFloat FTP Server PWD Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0. It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component PWD Command Handler. The manipulation leads to buffer overflow. The attack can be launched rem…
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High 7.3
FreeFloat FTP Server BYE Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0. It has been classified as critical. Affected is an unknown function of the component BYE Command Handler. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. The explo…
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Critical 9.8
IO::Compress::Brotli versions prior to 0.007 for Perl have an integer overflow in the bundled Brotli C library
A buffer overflow, as described in CVE-2020-8927, exists in the embedded Brotli library. Versions of IO::Compress::Brotli prior to 0.007 included a version of the brotli library prior to version 1.0.8, where an attacker controlling the input length of a "one…
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High 7.3
PCMan FTP Server NLST Command buffer overflow
A vulnerability has been found in PCMan FTP Server 2.0.7 and classified as critical. This vulnerability affects unknown code of the component NLST Command Handler. The manipulation leads to buffer overflow. The attack can be initiated remotely. The exploit ha…
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High 7.3
FreeFloat FTP Server RETR Command buffer overflow
A vulnerability, which was classified as critical, was found in FreeFloat FTP Server 1.0. This affects an unknown part of the component RETR Command Handler. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exploi…
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Medium 5.4CVE-2025-29632 Public exploit
Buffer Overflow vulnerability in Free5gc v.4.0.0 allows a remote attacker to cause a denial of service via the AMF, NGA…
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High 7.3
FreeFloat FTP Server PORT Command buffer overflow
A vulnerability classified as critical was found in FreeFloat FTP Server 1.0.0. This vulnerability affects unknown code of the component PORT Command Handler. The manipulation leads to buffer overflow. The attack can be initiated remotely. The exploit has bee…
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High 7.0CVE-2025-5222 Public exploit
Icu: stack buffer overflow in the srbroot::addtag function
A stack buffer overflow was found in Internationl components for unicode (ICU ). While running the genrb binary, the 'subtag' struct overflowed at the SRBRoot::addTag function. This issue may lead to memory corruption and local arbitrary code execution.
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High 7.3
FreeFloat FTP Server QUOTE Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0.0. It has been classified as critical. This affects an unknown part of the component QUOTE Command Handler. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The ex…
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High 7.3
FreeFloat FTP Server GET Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0.0 and classified as critical. Affected by this issue is some unknown functionality of the component GET Command Handler. The manipulation leads to buffer overflow. The attack may be launched remotely. The …
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High 7.3
FreeFloat FTP Server ASCII Command buffer overflow
A vulnerability has been found in FreeFloat FTP Server 1.0.0 and classified as critical. Affected by this vulnerability is an unknown functionality of the component ASCII Command Handler. The manipulation leads to buffer overflow. The attack can be launched r…
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High 7.3
FreeFloat FTP Server LITERAL Command buffer overflow
A vulnerability, which was classified as critical, was found in FreeFloat FTP Server 1.0.0. Affected is an unknown function of the component LITERAL Command Handler. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. The …
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High 7.3
FreeFloat FTP Server RMDIR Command buffer overflow
A vulnerability, which was classified as critical, has been found in FreeFloat FTP Server 1.0.0. This issue affects some unknown processing of the component RMDIR Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely…
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High 8.8
H3C GR-5400AX aspForm EditWlanMacList buffer overflow
A vulnerability was found in H3C GR-5400AX up to 100R008 and classified as critical. Affected by this issue is the function EditWlanMacList of the file /routing/goform/aspForm. The manipulation of the argument param leads to buffer overflow. The attack may be…
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High 7.3
FreeFloat FTP Server MGET Command buffer overflow
A vulnerability, which was classified as critical, was found in FreeFloat FTP Server 1.0. This affects an unknown part of the component MGET Command Handler. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exploi…
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High 7.3
FreeFloat FTP Server TYPE Command buffer overflow
A vulnerability, which was classified as critical, has been found in FreeFloat FTP Server 1.0. Affected by this issue is some unknown functionality of the component TYPE Command Handler. The manipulation leads to buffer overflow. The attack may be launched re…
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High 7.3
FreeFloat FTP Server VERBOSE Command buffer overflow
A vulnerability classified as critical was found in FreeFloat FTP Server 1.0. Affected by this vulnerability is an unknown functionality of the component VERBOSE Command Handler. The manipulation leads to buffer overflow. The attack can be launched remotely. …
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High 7.3
FreeFloat FTP Server STATUS Command buffer overflow
A vulnerability classified as critical has been found in FreeFloat FTP Server 1.0. Affected is an unknown function of the component STATUS Command Handler. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. The exploit ha…
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High 7.3
FreeFloat FTP Server SEND Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0 and classified as critical. Affected by this issue is some unknown functionality of the component SEND Command Handler. The manipulation leads to buffer overflow. The attack may be launched remotely. The e…
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High 7.3
FreeFloat FTP Server DEBUG Command buffer overflow
A vulnerability has been found in FreeFloat FTP Server 1.0 and classified as critical. Affected by this vulnerability is an unknown functionality of the component DEBUG Command Handler. The manipulation leads to buffer overflow. The attack can be launched rem…
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High 7.8
Sandboxie has Pool Buffer Overflow in SbieDrv.sys API (API_GET_SECURE_PARAM)
Sandboxie is a sandbox-based isolation software for 32-bit and 64-bit Windows NT-based operating systems. Starting in version 1.3.0 and prior to 1.15.12, API_GET_SECURE_PARAM has an arithmetic overflow leading to a small memory allocation and then a extremely…
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High 7.8
Sandboxie has Pool Buffer Overflow in SbieDrv.sys API (API_SET_SECURE_PARAM)
Sandboxie is a sandbox-based isolation software for 32-bit and 64-bit Windows NT-based operating systems. Starting in version 0.0.1 and prior to 1.15.12, API_SET_SECURE_PARAM may have an arithmetic overflow deep in the memory allocation subsystem that would l…