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)
-
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.
-
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.
-
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.
-
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.
-
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.
-
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.
-
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].
-
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
-
Medium 4.5
A buffer copy without checking size of input ('classic buffer overflow') in Fortinet FortiMail webmail and administrati…
-
High 7.5
Tenda W6_S v1.0.0.4_510 has a Buffer Overflow vulnerability in the set_local_time function, which allows remote attacke…
-
High 7.5
Tenda W6_S v1.0.0.4_510 has a Buffer Overflow vulnerability in the setcfm function, which allows remote attackers to ca…
-
High 7.8
Bluetooth: Fix a buffer overflow in mgmt_mesh_add()
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: Fix a buffer overflow in mgmt_mesh_add() Smatch Warning: net/bluetooth/mgmt_util.c:375 mgmt_mesh_add() error: __memcpy() 'mesh_tx->param' too small (48 vs 50) Analysis: 'mesh_tx->p…
-
High 7.5
Unauthorized stack overflow vulnerability in Telesquare TLR-2005KSH v.1.1.4 allows a remote attacker to obtain sensitiv…
-
Critical 9.8
Telesquare TLR-2005KSH 1.1.4 has an unauthorized stack overflow vulnerability when requesting the admin.cgi parameter w…
-
Critical 9.8
Telesquare TLR-2005KSH 1.1.4 has an unauthorized stack overflow vulnerability when requesting the admin.cgi parameter w…
-
Critical 9.8
In Telesquare TLR-2005KSH 1.1.4, an unauthorized stack overflow vulnerability exists when requesting admin.cgi paramete…
-
Critical 9.8
Telesquare TLR-2005KSH 1.1.4 is vulnerable to unauthorized stack overflow vulnerability when requesting admin.cgi param…
-
Critical 9.8
Telesquare TLR-2005KSH 1.1.4 has an unauthorized stack overflow vulnerability in the login interface when requesting sy…
-
Critical 9.8
Telesquare TLR-2005KSH 1.1.4 is vulnerable to unauthorized stack buffer overflow vulnerability when requesting admin.cg…
-
Critical 9.8
Telesquare TLR-2005KSH 1.1.4 is affected by an unauthorized stack overflow vulnerability when requesting the admin.cgi …
-
High 7.8
An issue was discovered in Artifex Ghostscript before 10.05.0. A buffer overflow occurs when converting glyphs to Unico…
-
Critical 9.8
An issue was discovered in Artifex Ghostscript before 10.05.0. The NPDL device has a Compression buffer overflow for co…
-
Critical 9.8
An issue was discovered in Artifex Ghostscript before 10.05.0. The DOCXWRITE TXTWRITE device has a text buffer overflow…
-
High 7.8
An issue was discovered in Artifex Ghostscript before 10.05.0. A buffer overflow occurs during serialization of DollarB…
-
High 7.8
An issue was discovered in Artifex Ghostscript before 10.05.0. A buffer overflow occurs via an oversized Type 4 functio…
-
High 7.8
An issue was discovered in Artifex Ghostscript before 10.05.0. A buffer overflow occurs for a long TTF font name to pdf…
-
Critical 9.8
An issue was discovered in Artifex Ghostscript before 10.05.0. The BJ10V device has a Print buffer overflow in contrib/…
-
Critical 9.8
Tenda AC7 V1.0 V15.03.06.44 found a buffer overflow caused by the timeZone parameter in the form_fast_setting_wifi_set …
-
Medium 6.8
A buffer overflow in the GuitarPro1::read function of MuseScore Studio v4.3.2 allows attackers to to execute arbitrary …
-
Medium 5.9
Tenda AC9 v15.03.05.19(6318) was discovered to contain a buffer overflow via the formWifiWpsOOB function.
-
High 7.8
SLDPRT File Parsing Memory Corruption Vulnerability
A maliciously crafted SLDPRT file, when parsed through Autodesk AutoCAD, can force a Memory Corruption vulnerability. A malicious actor can leverage this vulnerability to execute arbitrary code in the context of the current process.
-
High 7.5
Tenda RX3 US_RX3V1.0br_V16.03.13.11_multi_TDE01 is vulnerable to Buffer Overflow via the time and timeZone parameters a…
-
High 7.5
Tenda RX3 US_RX3V1.0br_V16.03.13.11_multi_TDE01 is vulnerable to Buffer Overflow via the list parameter at /goform/setP…
-
High 7.5
Tenda RX3 US_RX3V1.0br_V16.03.13.11_multi_TDE01 is vulnerable to buffer overflow via the schedStartTime and schedEndTim…
-
High 7.5
Tenda RX3 US_RX3V1.0br_V16.03.13.11_multi_TDE01 is vulnerable to Buffer Overflow via the firewallEn parameter at /gofor…
-
High 7.5
Tenda RX3 US_RX3V1.0br_V16.03.13.11_multi_TDE01 is vulnerable to Buffer Overflow via the list parameter at /goform/SetV…
-
High 7.5
Tenda RX3 US_RX3V1.0br_V16.03.13.11_multi_TDE01 is vulnerable to Buffer Overflow via the deviceId parameter at /goform/…
-
High 8.6CVE-2025-20115 Public exploit
Cisco IOS XR Software Border Gateway Protocol Denial of Service Vulnerability
A vulnerability in confederation implementation for the Border Gateway Protocol (BGP) in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to a memory corruption …
-
Critical 9.8
SoftEther VPN 5.02.5187 is vulnerable to Buffer Overflow in Internat.c via the UniToStrForSingleChars function. NOTE: t…
-
Critical 9.8
SoftEther VPN 5.02.5187 is vulnerable to Buffer Overflow in the Command.c file via the PtMakeCert and PtMakeCert2048 fu…
-
High 7.8
Ashlar-Vellum Cobalt CO File Parsing Buffer Overflow Remote Code Execution Vulnerability
Ashlar-Vellum Cobalt CO File Parsing Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ashlar-Vellum Cobalt. User interaction is required to exploit this vuln…
-
Medium 6.3
HBS 3 Hybrid Backup Sync
A buffer overflow vulnerability has been reported to affect HBS 3 Hybrid Backup Sync. If exploited, the vulnerability could allow remote attackers to modify memory or crash processes. We have already fixed the vulnerability in the following version: HBS 3 Hyb…
-
Low 3.3
Arkcompiler Ets Runtime has a buffer overflow vulnerability
in OpenHarmony v5.0.2 and prior versions allow a local attacker cause DOS through buffer overflow.
-
Low 3.3
Arkcompiler Ets Runtime has a buffer overflow vulnerability
in OpenHarmony v5.0.2 and prior versions allow a local attacker cause DOS through buffer overflow.
-
Medium 6.5
Tenda TX3 setPptpUserList buffer overflow
A vulnerability has been found in Tenda TX3 16.03.13.11_multi and classified as critical. Affected by this vulnerability is an unknown functionality of the file /goform/setPptpUserList. The manipulation of the argument list leads to buffer overflow. The attac…
-
Medium 6.5
Tenda TX3 openSchedWifi buffer overflow
A vulnerability, which was classified as critical, was found in Tenda TX3 16.03.13.11_multi. Affected is an unknown function of the file /goform/openSchedWifi. The manipulation of the argument schedStartTime/schedEndTime leads to buffer overflow. It is possib…
-
Medium 6.5
Tenda TX3 SetNetControlList buffer overflow
A vulnerability, which was classified as critical, has been found in Tenda TX3 16.03.13.11_multi. This issue affects some unknown processing of the file /goform/SetNetControlList. The manipulation of the argument list leads to buffer overflow. The attack may …
-
Medium 6.5
Tenda TX3 SetStaticRouteCfg buffer overflow
A vulnerability classified as critical was found in Tenda TX3 16.03.13.11_multi. This vulnerability affects unknown code of the file /goform/SetStaticRouteCfg. The manipulation of the argument list leads to buffer overflow. The attack can be initiated remotel…