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 7.3
FreeFloat FTP Server PROMPT 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 PROMPT 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 MKDIR 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 MKDIR Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. …
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High 7.3
FreeFloat FTP Server MDIR 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 MDIR Command Handler. The manipulation leads to buffer overflow. The attack may be launched re…
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High 7.3
FreeFloat FTP Server LS 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 LS Command Handler. The manipulation leads to buffer overflow. The attack can be launched remotely. The e…
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High 7.3
FreeFloat FTP Server BINARY 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 BINARY 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 BELL Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0. It has been rated as critical. This issue affects some unknown processing of the component BELL 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 APPEND Command buffer overflow
A vulnerability was found in FreeFloat FTP Server 1.0. It has been declared as critical. This vulnerability affects unknown code of the component APPEND Command Handler. The manipulation leads to buffer overflow. The attack can be initiated remotely. The expl…
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High 8.2
Stack overflow leading to DoS can be triggered by a malicious authenticated client.
Stack overflow leading to DoS can be triggered by a malicious authenticated client in Clickhouse before 19.14.3.3.
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High 8.8
Tenda A15 HTTP POST Request multimodalAdd buffer overflow
A vulnerability was found in Tenda A15 15.13.07.09/15.13.07.13. It has been classified as critical. This affects an unknown part of the file /goform/multimodalAdd of the component HTTP POST Request Handler. The manipulation leads to buffer overflow. It is pos…
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High 8.8
Tenda AC10 UserCongratulationsExec buffer overflow
A vulnerability was found in Tenda AC10 16.03.10.13 and classified as critical. Affected by this issue is some unknown functionality of the file /goform/UserCongratulationsExec. The manipulation of the argument getuid leads to buffer overflow. The attack may …
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Medium 5.3
code-projects Police Station Management System Display Record source.cpp display buffer overflow
A vulnerability was found in code-projects Police Station Management System 1.0. It has been classified as critical. Affected is the function criminal::display of the file source.cpp of the component Display Record. The manipulation of the argument N leads to…
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Medium 5.3
code-projects Tourism Management System User Registration AddUser buffer overflow
A vulnerability has been found in code-projects Tourism Management System 1.0 and classified as critical. This vulnerability affects the function AddUser of the component User Registration. The manipulation of the argument username/password leads to buffer ov…
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Medium 5.3
code-projects Pharmacy Management System Add Order Details take_order buffer overflow
A vulnerability, which was classified as critical, was found in code-projects Pharmacy Management System 1.0. This affects the function medicineType::take_order of the component Add Order Details. The manipulation leads to buffer overflow. An attack has to be…
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High 7.3
FreeFloat FTP Server CCC 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 CCC Command Handler. The manipulation leads to buffer overflow. It is possible to launch the attack remotely. The exploi…
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High 7.3CVE-2025-4871 Public exploit
PCMan FTP Server REST Command buffer overflow
A vulnerability, which was classified as critical, has been found in PCMan FTP Server 2.0.7. This issue affects some unknown processing of the component REST Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. The…
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High 7.3
FreeFloat FTP Server RECV 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 RECV Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. The exploit ha…
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High 7.3
FreeFloat FTP Server MLS 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 MLS 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 MPUT 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 MPUT 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 TRACE 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 TRACE Command Handler. The manipulation leads to buffer overflow. The attack may be launched r…
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High 7.3
FreeFloat FTP Server CD 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 CD Command Handler. The manipulation leads to buffer overflow. The attack can be launched remotely. The e…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formWlanRedirect buffer overflow
A vulnerability was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. It has been declared as critical. Affected by this vulnerability is an unknown functionality of the file /boafrm/formWlanRedirect of the component HTTP POST Request Handler.…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formSetLg buffer overflow
A vulnerability was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. It has been classified as critical. Affected is an unknown function of the file /boafrm/formSetLg of the component HTTP POST Request Handler. The manipulation of the argumen…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formNtp buffer overflow
A vulnerability was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615 and classified as critical. This issue affects some unknown processing of the file /boafrm/formNtp of the component HTTP POST Request Handler. The manipulation of the argumen…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formDosCfg buffer overflow
A vulnerability has been found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615 and classified as critical. This vulnerability affects unknown code of the file /boafrm/formDosCfg of the component HTTP POST Request Handler. The manipulation of the ar…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formSiteSurveyProfile buffer overflow
A vulnerability, which was classified as critical, was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. This affects an unknown part of the file /boafrm/formSiteSurveyProfile of the component HTTP POST Request Handler. The manipulation of the…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formSysCmd buffer overflow
A vulnerability, which was classified as critical, has been found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. Affected by this issue is some unknown functionality of the file /boafrm/formSysCmd of the component HTTP POST Request Handler. The m…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formStats sub_40BE30 buffer overflow
A vulnerability classified as critical was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. Affected by this vulnerability is the function sub_40BE30 of the file /boafrm/formStats of the component HTTP POST Request Handler. The manipulation o…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formSaveConfig buffer overflow
A vulnerability, which was classified as critical, was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. Affected is an unknown function of the file /boafrm/formSaveConfig of the component HTTP POST Request Handler. The manipulation of the arg…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formWirelessTbl buffer overflow
A vulnerability, which was classified as critical, has been found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. This issue affects some unknown processing of the file /boafrm/formWirelessTbl of the component HTTP POST Request Handler. The manipu…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formDMZ buffer overflow
A vulnerability classified as critical was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. This vulnerability affects unknown code of the file /boafrm/formDMZ of the component HTTP POST Request Handler. The manipulation of the argument submi…
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formWsc buffer overflow
A vulnerability classified as critical has been found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. This affects an unknown part of the file /boafrm/formWsc of the component HTTP POST Request Handler. The manipulation of the argument submit-url …
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High 8.8
TOTOLINK A702R/A3002R/A3002RU HTTP POST Request formReflashClientTbl submit-url buffer overflow
A vulnerability was found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. It has been rated as critical. Affected by this issue is the function submit-url of the file /boafrm/formReflashClientTbl of the component HTTP POST Request Handler. The man…
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High 7.3
FreeFloat FTP Server MDELETE 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 MDELETE Command Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. The exploit…
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High 7.3
FreeFloat FTP Server HASH 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 HASH Command Handler. The manipulation leads to buffer overflow. The attack can be initiated remotely. The exploit …
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High 7.3
FreeFloat FTP Server GLOB 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 GLOB 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 LCD 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 LCD Command Handler. The manipulation leads to buffer overflow. The attack may be launched rem…
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High 7.3
FreeFloat FTP Server DELETE 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 DELETE Command Handler. The manipulation leads to buffer overflow. The attack can be launched remotely. T…
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High 8.8
TOTOLINK A3002R/A3002RU HTTP POST Request formIpQoS buffer overflow
A vulnerability, which was classified as critical, has been found in TOTOLINK A3002R and A3002RU 3.0.0-B20230809.1615. This issue affects some unknown processing of the file /boafrm/formIpQoS of the component HTTP POST Request Handler. The manipulation of the…
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High 8.8
TOTOLINK A3002R/A3002RU HTTP POST Request formFilter buffer overflow
A vulnerability classified as critical was found in TOTOLINK A3002R and A3002RU 3.0.0-B20230809.1615. This vulnerability affects unknown code of the file /boafrm/formFilter of the component HTTP POST Request Handler. The manipulation of the argument ip6addr l…
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High 8.8
TOTOLINK A3002R/A3002RU HTTP POST Request formPortFw buffer overflow
A vulnerability classified as critical has been found in TOTOLINK A3002R and A3002RU 3.0.0-B20230809.1615. This affects an unknown part of the file /boafrm/formPortFw of the component HTTP POST Request Handler. The manipulation of the argument service_type/ip…