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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Critical 9.3
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in rethinkdb.This issue affects re…
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Medium 6.5
A buffer overflow in the Mercury MR816v2 (081C3114 4.8.7 Build 110427 Rel 36550n) occurs when the device accepts and st…
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High 8.8
H3C Magic B1 aspForm sub_44de0 buffer overflow
A weakness has been identified in H3C Magic B1 up to 100R004. The affected element is the function sub_44de0 of the file /goform/aspForm. This manipulation of the argument param causes buffer overflow. Remote exploitation of the attack is possible. The exploi…
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High 8.8
UTT 进取 512W formP2PLimitConfig strcpy buffer overflow
A vulnerability has been found in UTT 进取 512W up to 1.7.7-171114. Affected by this issue is the function strcpy of the file /goform/formP2PLimitConfig. Such manipulation of the argument except leads to buffer overflow. It is possible to launch the attack remo…
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High 7.2
UGREEN DH2100+ nas_svr create handler_file_backup_create buffer overflow
A weakness has been identified in UGREEN DH2100+ up to 5.3.0.251125. This affects the function handler_file_backup_create of the file /v1/file/backup/create of the component nas_svr. Executing a manipulation of the argument path can lead to buffer overflow. T…
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High 8.8
UTT 进取 520W formArpBindConfig strcpy buffer overflow
A flaw has been found in UTT 进取 520W 1.7.7-180627. The impacted element is the function strcpy of the file /goform/formArpBindConfig. Executing manipulation of the argument pools can lead to buffer overflow. The attack may be performed from remote. The exploi…
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Medium 6.5
UTT 进取 520W websHostFilter strcpy buffer overflow
A vulnerability was detected in UTT 进取 520W 1.7.7-180627. The affected element is the function strcpy of the file /goform/websHostFilter. Performing manipulation of the argument addHostFilter results in buffer overflow. The attack is possible to be carried ou…
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Medium 5.7
UTT 进取 520W formConfigDnsFilterGlobal strcpy buffer overflow
A security vulnerability has been detected in UTT 进取 520W 1.7.7-180627. Impacted is the function strcpy of the file /goform/formConfigDnsFilterGlobal. Such manipulation of the argument timeRangeName leads to buffer overflow. The exploit has been disclosed pub…
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High 7.5
A Buffer overflow vulnerability on Fanvil x210 2.12.20 devices allows attackers to cause a denial of service or potenti…
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High 8.8
H3C Magic B0 aspForm EditWlanMacList buffer overflow
A weakness has been identified in H3C Magic B0 up to 100R002. This impacts the function EditWlanMacList of the file /goform/aspForm. This manipulation of the argument param causes buffer overflow. Remote exploitation of the attack is possible. The exploit has…
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High 8.8
Webkitgtk: processing maliciously crafted web content may lead to an unexpected process crash
A flaw was found in WebKitGTK. Processing malicious web content can cause an unexpected process crash due to improper memory handling.
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Medium 5.1CVE-2025-50361 Public exploit
Buffer Overflow was found in SmallBASIC community SmallBASIC with SDL Before v12_28, and commit sha:298a1d495355959db36…
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High 8.7
Stack-based buffer overflow vulnreability in Circutor SGE-PLC1000/SGE-PLC50
Stack-based buffer overflow vulnerability in Circutor SGE-PLC1000/SGE-PLC50 v9.0.2. In the 'showMeterReport()' function, there is an unlimited user input that is copied to a fixed-size buffer via 'sprintf()'. The 'GetParameter(meter)' function retrieves the u…
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Medium 6.5
A buffer overflow in the g_cfg.MaxUsers component of LightFTP v2.0 allows attackers to cause a Denial of Service (DoS) …
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Medium 6.5
A buffer overflow in the getSideInfo2() function of Live555 Streaming Media v2018.09.02 allows attackers to cause a Den…
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High 7.6
Bluetooth: Mesh: Out-of-Bound Write in gen_prov_cont
An out-of-bound write can lead to an arbitrary code execution. Even on devices with some form of memory protection, this can still lead to a crash and a resultant denial of service.
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High 7.6
Bluetooth: Mesh: Out-of-Bound Write in gen_prov_start
There is a potential OOB Write vulnerability in the gen_prov_start function in pb_adv.c. The full length of the received data is copied into the link.rx.buf receiver buffer without any validation on the data size.
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Critical 9.8
FAST FAC1200R F400_FAC1200R_Q is vulnerable to Buffer Overflow in the function sub_80435780 via the parameter string fa…
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Critical 9.8
FAST FAC1200R F400_FAC1200R_Q is vulnerable to Buffer Overflow in the function sub_80435780 via the parameter password.
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High 8.8
D-Link DWR-M920 formPinManageSetup sub_41C7FC buffer overflow
A weakness has been identified in D-Link DWR-M920 1.1.50. This affects the function sub_41C7FC of the file /boafrm/formPinManageSetup. This manipulation of the argument submit-url causes buffer overflow. It is possible to initiate the attack remotely. The exp…
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High 8.8
D-Link DIR-822K/DWR-M920 formWlEncrypt buffer overflow
A security flaw has been discovered in D-Link DIR-822K and DWR-M920 1.00_20250513164613/1.1.50. The impacted element is an unknown function of the file /boafrm/formWlEncrypt. The manipulation of the argument submit-url results in buffer overflow. The attack m…
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High 8.8
D-Link DIR-822K/DWR-M920 formWanConfigSetup buffer overflow
A vulnerability was identified in D-Link DIR-822K and DWR-M920 1.00_20250513164613/1.1.50. The affected element is an unknown function of the file /boafrm/formWanConfigSetup. The manipulation of the argument submit-url leads to buffer overflow. The attack is …
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High 8.8
D-Link DIR-822K/DWR-M920 formVpnConfigSetup buffer overflow
A vulnerability was determined in D-Link DIR-822K and DWR-M920 1.00_20250513164613/1.1.50. Impacted is an unknown function of the file /boafrm/formVpnConfigSetup. Executing manipulation of the argument submit-url can lead to buffer overflow. The attack can be…
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High 8.8
D-Link DIR-822K formNtp sub_455524 buffer overflow
A vulnerability was found in D-Link DIR-822K 1.00. This issue affects the function sub_455524 of the file /boafrm/formNtp. Performing manipulation of the argument submit-url results in buffer overflow. Remote exploitation of the attack is possible. The exploi…
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High 8.8
D-Link DIR-822K/DWR-M920 formFirewallAdv buffer overflow
A vulnerability has been found in D-Link DIR-822K and DWR-M920 1.00_20250513164613/1.1.50. This vulnerability affects unknown code of the file /boafrm/formFirewallAdv. Such manipulation of the argument submit-url leads to buffer overflow. The attack may be la…
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High 8.7
PJSIP is vulnerable to buffer overflow in Opus PLC
PJSIP is a free and open source multimedia communication library. Prior to version 2.16, Opus PLC may zero-fill the input frame as long as the decoder ptime, while the input frame length, which is based on stream ptime, may be less than that. This issue affec…
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Medium 4.3
Tenda AC21 V16.03.08.16 is vulnerable to Buffer Overflow via the deviceId parameter in /goform/saveParentControlInfo.
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High 8.8
Tenda CH22 WrlExtraGet formWrlExtraGet buffer overflow
A vulnerability was detected in Tenda CH22 1.0.0.1. Affected is the function formWrlExtraGet of the file /goform/WrlExtraGet. Performing a manipulation of the argument chkHz results in buffer overflow. Remote exploitation of the attack is possible. The exploi…
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Medium 6.3
A buffer copy without checking size of input ('classic buffer overflow') vulnerability in Fortinet FortiExtender 7.6.0 …
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High 8.8
D-Link DWR-M920/DWR-M921/DWR-M960/DIR-822K/DIR-825M formTracerouteDiagnosticRun buffer overflow
A weakness has been identified in D-Link DWR-M920, DWR-M921, DWR-M960, DIR-822K and DIR-825M 1.01.07. This issue affects some unknown processing of the file /boafrm/formTracerouteDiagnosticRun. Executing manipulation of the argument host can lead to buffer ov…
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High 8.8
Dell ControlVault3 CvManager_SBI buffer overflow vulnerability
A buffer overflow vulnerability exists in the CvManager_SBI functionality of Dell ControlVault3 prior to 5.15.14.19 and Dell ControlVault3 Plus prior to 6.2.36.47. A specially crafted ControlVault API call can lead to a arbitrary code execution. An attacker c…
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High 8.8
D-Link DWR-M920/DWR-M921/DWR-M960/DWR-M961/DIR-825M formPingDiagnosticRun buffer overflow
A security flaw has been discovered in D-Link DWR-M920, DWR-M921, DWR-M960, DWR-M961 and DIR-825M 1.01.07/1.1.47. This vulnerability affects unknown code of the file /boafrm/formPingDiagnosticRun. Performing manipulation of the argument host results in buffer…
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High 8.8
Dell ControlVault3 CvManager buffer overflow vulnerability
A buffer overflow vulnerability exists in the CvManager functionality of Dell ControlVault3 prior to 5.15.14.19 and Dell ControlVault3 Plus prior to 6.2.36.47. A specially crafted ControlVault API call can lead to memory corruption. An attacker can issue an a…
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High 8.8
Tenda CH22 PPTPUserSetting fromPptpUserSetting buffer overflow
A security vulnerability has been detected in Tenda CH22 1.0.0.1. This impacts the function fromPptpUserSetting of the file /goform/PPTPUserSetting. The manipulation of the argument delno leads to buffer overflow. The attack is possible to be carried out remo…
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High 8.8
Tenda AC20 WifiExtraSet buffer overflow
A vulnerability was detected in Tenda AC20 up to 16.03.08.12. The impacted element is an unknown function of the file /goform/WifiExtraSet. The manipulation of the argument wpapsk_crypto results in buffer overflow. The attack can be launched remotely. The exp…
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High 8.7
Netis DL4322D RTK 2.1.1 FTP Service DoS
Netis ADSL Router DL4322D firmware RTK 2.1.1 contains a buffer overflow vulnerability in the embedded FTP service that allows an authenticated remote user to trigger a denial of service. After logging in to the FTP service, sending an FTP command such as ABOR…
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Critical 9.8
free5gc v4.1.0 and before is vulnerable to Buffer Overflow. When AMF receives an UplinkRANConfigurationTransfer NGAP me…
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High 7.2
A vulnerability has been identified in LOGO! 12/24RCE (6ED1052-1MD08-0BA2) (All versions < V1.84.05), LOGO! 12/24RCEo (…
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Medium 6.6
Buffer overflow for some Intel(R) QAT Windows software before version 2.6.0. within Ring 3: User Applications may allow…
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Medium 6.5
Buffer overflow for some Intel(R) QAT Windows software before version 2.6.0. within Ring 3: User Applications may allow…