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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Medium 6.5
The issue was addressed with improved memory handling. This issue is fixed in Safari 26.5, iOS 18.7.9 and iPadOS 18.7.9…
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Medium 6.5
The issue was addressed with improved memory handling. This issue is fixed in Safari 26.5, iOS 26.5 and iPadOS 26.5, ma…
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High 8.8
The issue was addressed with improved memory handling. This issue is fixed in Safari 26.5, iOS 18.7.9 and iPadOS 18.7.9…
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High 8.8
The issue was addressed with improved memory handling. This issue is fixed in Safari 26.5, iOS 18.7.9 and iPadOS 18.7.9…
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High 7.5
A buffer overflow was addressed with improved bounds checking. This issue is fixed in iOS 18.7.9 and iPadOS 18.7.9, iOS…
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High 8.1
Neat VNC: Buffer overflow due to oversized RSA public keys
Neat VNC is a VNC server library. Prior to 0.9.6, a pre-authentication stack buffer overflow exists in neatvnc in the RSA-AES security type handler. An unauthenticated remote attacker who can reach the VNC listening socket can send a crafted security type 5 (…
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High 8.8
D-Link DCS-935L HNAP Service hnap_service SetDeviceSettings buffer overflow
A vulnerability was found in D-Link DCS-935L up to 1.10.01. The impacted element is the function SetDeviceSettings of the file /web/cgi-bin/hnap/hnap_service of the component HNAP Service. The manipulation of the argument AdminPassword results in buffer overf…
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High 8.8
Totolink X5000R formDdns sub_458E40 buffer overflow
A vulnerability has been found in Totolink X5000R 9.1.0u.6369_B20230113. This vulnerability affects the function sub_458E40 of the file /boafrm/formDdns. The manipulation of the argument submit-url leads to buffer overflow. Remote exploitation of the attack i…
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High 8.1
Memory safety bugs fixed in Thunderbird 150.0.2
Memory safety bugs present in Thunderbird 150.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 150.0.2 an…
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High 7.8
MongoDB C Driver Cyrus SASL Canonicalization Buffer Overflow
The MongoDB C Driver's Cyrus SASL integration performs unsafe string copying during username canonicalization, enabling a heap buffer overflow before any authentication or network traffic. This may be triggered by passing untrusted input in the username of a …
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High 7.2
D-Link DI-8100 CGI user_group.asp sprintf buffer overflow
A vulnerability has been found in D-Link DI-8100 16.07.26A1. This vulnerability affects the function sprintf of the file /user_group.asp of the component CGI Handler. The manipulation leads to buffer overflow. The attack may be initiated remotely. The exploit…
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High 7.2
D-Link DI-8100 Web Management url_member.asp buffer overflow
A flaw has been found in D-Link DI-8100 16.07.26A1. This affects an unknown part of the file /url_member.asp of the component Web Management Interface. Executing a manipulation of the argument Name can lead to buffer overflow. The attack can be launched remot…
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High 8.8
D-Link DI-8100 HTTP Request tggl.asp tggl_asp buffer overflow
A vulnerability was detected in D-Link DI-8100 16.07.26A1. Affected by this issue is the function tggl_asp of the file /tggl.asp of the component HTTP Request Handler. Performing a manipulation of the argument Name results in buffer overflow. The attack can b…
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Critical 9.8
D-Link DI-8100 POST Parameter url_rule.asp url_rule_asp buffer overflow
A security vulnerability has been detected in D-Link DI-8100 16.07.26A1. Affected by this vulnerability is the function url_rule_asp of the file /url_rule.asp of the component POST Parameter Handler. Such manipulation leads to buffer overflow. It is possible …
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Critical 9.8
D-Link DI-8100 HTTP auto_reboot.asp sprintf buffer overflow
A weakness has been identified in D-Link DI-8100 16.07.26A1. Affected is the function sprintf of the file /auto_reboot.asp of the component HTTP Handler. This manipulation of the argument enable/time causes buffer overflow. It is possible to initiate the atta…
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Medium 5.9
Openvswitch: open vswitch: denial of service via malformed ftp epasv command
A flaw was found in Open vSwitch. When Open vSwitch is configured with a conntrack flow using FTP helpers over the userspace datapath, a remote attacker can send a specially crafted FTP stream with an EPASV command exceeding 255 characters. This heap access e…
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Medium 6.5
Buffer Copy Without Checking Size of Input in Automotive Audio
Memory corruption when dynamically changing the size of a previously allocated buffer while its contents are being modified.
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High 8.8
Totolink N300RH POST Request cstecgi.cgi setMacFilterRules buffer overflow
A vulnerability was detected in Totolink N300RH 3.2.4-B20220812. This vulnerability affects the function setMacFilterRules of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. The manipulation of the argument mac_address results in buffer o…
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High 8.8
Totolink N300RH POST Request cstecgi.cgi setWanConfig buffer overflow
A security vulnerability has been detected in Totolink N300RH 3.2.4-B20220812. This affects the function setWanConfig of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. The manipulation of the argument priDns leads to buffer overflow. The…
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High 8.8
Totolink N300RH POST Request cstecgi.cgi setUpgradeFW buffer overflow
A weakness has been identified in Totolink N300RH 3.2.4-B20220812. Affected by this issue is the function setUpgradeFW of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. Executing a manipulation of the argument FileName can lead to buffer…
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Critical 9.8
Totolink N300RH Parameter cstecgi.cgi loginauth buffer overflow
A security flaw has been discovered in Totolink N300RH 3.2.4-B20220812. Affected by this vulnerability is the function loginauth of the file /cgi-bin/cstecgi.cgi of the component Parameter Handler. Performing a manipulation of the argument Password results in…
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Medium 6.5
In Modem, there is a possible system crash due to a heap buffer overflow. This could lead to remote denial of service, …
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High 7.3
osrg GoBGP AIGP Attribute bgp.go PathAttributeAigp.DecodeFromBytes buffer overflow
A vulnerability was found in osrg GoBGP up to 4.3.0. Affected is the function PathAttributeAigp.DecodeFromBytes of the file pkg/packet/bgp/bgp.go of the component AIGP Attribute Parser. Performing a manipulation results in buffer overflow. It is possible to i…
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Critical 9.8
Totolink WA300 POST Request cstecgi.cgi loginauth buffer overflow
A security flaw has been discovered in Totolink WA300 5.2cu.7112_B20190227. The affected element is the function loginauth of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. The manipulation of the argument http_host results in buffer ove…
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High 8.8
Totolink WA300 POST Request cstecgi.cgi UploadCustomModule buffer overflow
A vulnerability was determined in Totolink WA300 5.2cu.7112_B20190227. This issue affects the function UploadCustomModule of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. Executing a manipulation of the argument File can lead to buffer …
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High 8.8
Edimax BR-6208AC setWAN buffer overflow
A vulnerability was detected in Edimax BR-6208AC up to 1.02. Affected is an unknown function of the file /goform/setWAN. Performing a manipulation of the argument pptpDfGateway results in buffer overflow. The attack may be initiated remotely. The exploit is …
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High 8.8
Edimax BR-6428nC setWAN buffer overflow
A security vulnerability has been detected in Edimax BR-6428nC up to 1.16. This impacts an unknown function of the file /goform/setWAN. Such manipulation of the argument pptpDfGateway leads to buffer overflow. The attack can be launched remotely. The exploit…
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High 8.8
Shenzhen Libituo Technology LBT-T300-HW1 apply.cgi start_lan buffer overflow
A vulnerability has been found in Shenzhen Libituo Technology LBT-T300-HW1 up to 1.2.8. Impacted is the function start_lan of the file /apply.cgi. The manipulation of the argument Channel/ApCliSsid leads to buffer overflow. The attack is possible to be carrie…
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High 8.8
Shenzhen Libituo Technology LBT-T300-HW1 Web Management start_single_service buffer overflow
A flaw has been found in Shenzhen Libituo Technology LBT-T300-HW1 up to 1.2.8. This issue affects the function start_single_service of the component Web Management Interface. Executing a manipulation of the argument vpn_pptp_server/vpn_l2tp_server can lead to…
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High 8.8
TRENDnet TEW-821DAP Firmware Udpate auto_update_firmware buffer overflow
A security vulnerability has been detected in TRENDnet TEW-821DAP 1.12B01. Impacted is the function auto_update_firmware of the component Firmware Udpate. The manipulation of the argument str leads to buffer overflow. The attack may be initiated remotely. The…
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High 8.8
UTT HiPER 1200GW formRemoteControl strcpy buffer overflow
A vulnerability has been found in UTT HiPER 1200GW up to 2.5.3-170306. The impacted element is the function strcpy of the file /goform/formRemoteControl. The manipulation leads to buffer overflow. The attack may be initiated remotely. The exploit has been dis…
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High 8.8
UTT HiPER 1200GW formUser strcpy buffer overflow
A flaw has been found in UTT HiPER 1200GW up to 2.5.3-1703. The affected element is the function strcpy of the file /goform/formUser. Executing a manipulation can lead to buffer overflow. The attack can be launched remotely. The exploit has been published and…
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Medium 4.7
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in Wireshark
K12 RF5 file parser crash in Wireshark 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14 allows denial of service
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High 8.8
code-projects for Plugin cstecgi.cgi setWiFiMultipleConfig buffer overflow
A vulnerability was detected in code-projects for Plugin 4.1.2cu.5137. The impacted element is the function setWiFiMultipleConfig in the library /lib/cste_modules/wireless.so of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument wepkey2 results i…
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Low 2.3
Buffer overflow in client authentication prior to version 14.50
CVE-2026-33446 is a buffer overflow in the authentication sub-system of the Secure Access client prior to 14.50. Attackers with control of a modified server can send a special packet that can overwrite a small portion of memory conceivably leading to memory c…
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High 7.8
Buffer overflow in drivers/xen/sys-hypervisor.c
In the Linux kernel, the following vulnerability has been resolved: Buffer overflow in drivers/xen/sys-hypervisor.c The build id returned by HYPERVISOR_xen_version(XENVER_build_id) is neither NUL terminated nor a string. The first causes a buffer overflow as …
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High 8.8
UTT HiPER 1250GW ConfigAdvideo strcpy buffer overflow
A security flaw has been discovered in UTT HiPER 1250GW up to 3.2.7-210907-180535. Impacted is the function strcpy of the file route/goform/ConfigAdvideo. The manipulation of the argument Profile results in buffer overflow. The attack can be executed remotely…
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High 8.8
UTT HiPER 1250GW formTaskEdit_ap strcpy buffer overflow
A vulnerability was identified in UTT HiPER 1250GW up to 3.2.7-210907-180535. This issue affects the function strcpy of the file route/goform/formTaskEdit_ap. The manipulation of the argument Profile leads to buffer overflow. Remote exploitation of the attack…
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High 8.8
UTT HiPER 1250GW NTP strcpy buffer overflow
A vulnerability was determined in UTT HiPER 1250GW up to 3.2.7-210907-180535. This vulnerability affects the function strcpy of the file route/goform/NTP. Executing a manipulation of the argument Profile can lead to buffer overflow. The attack may be launched…
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High 8.4
Alloksoft Video joiner 4.6.1217 Buffer Overflow via License Name
Alloksoft Video joiner 4.6.1217 contains a buffer overflow vulnerability that allows local attackers to execute arbitrary code by supplying a malicious string in the License Name field. Attackers can craft a payload with structured exception handler (SEH) ove…