Skip to content
OpenAdvisories

Weakness (CWE)

CWE-120: Buffer Copy without Checking Size of Input

Base Incomplete

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)
  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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].

  8. 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

1,826 results · Clear filters · Feed

  • High 7.5

    Tenda AC6V1.0 V15.03.05.19 was discovered to contain a buffer overflow via the devName parameter in the formSetDeviceNa…

  • High 7.1

    Buffer overflow in `CONV_3D_TRANSPOSE` on TFLite

    TensorFlow is an open source platform for machine learning. The reference kernel of the `CONV_3D_TRANSPOSE` TensorFlow Lite operator wrongly increments the data_ptr when adding the bias to the result. Instead of `data_ptr += num_channels;` it should be `data_…

  • High 8.4
  • High 8.1
    CVE-2022-0324 Public exploit

    Buffer Overflow in Dhcp6relay in Software for Open Networking in the Cloud (SONiC)

    There is a vulnerability in DHCPv6 packet parsing code that could be explored by remote attacker to craft a packet that could cause buffer overflow in a memcpy call, leading to out-of-bounds memory write that would cause dhcp6relay to crash. Dhcp6relay is a c…

  • High 7.7

    A vulnerability in the SSL/TLS client of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat De…

  • High 7.0

    sysstat Incorrect Buffer Size calculation on 32-bit systems results in RCE via buffer overflow

    sysstat is a set of system performance tools for the Linux operating system. On 32 bit systems, in versions 9.1.16 and newer but prior to 12.7.1, allocate_structures contains a size_t overflow in sa_common.c. The allocate_structures function insufficiently ch…

  • High 7.5
    CVE-2022-43343 Public exploit

    N-Prolog v1.91 was discovered to contain a global buffer overflow vulnerability in the function gettoken() at Main.c.

  • High 7.8

    A buffer overflow was discovered in NTFS-3G before 2022.10.3. Crafted metadata in an NTFS image can cause code executio…

  • High 7.8

    jhead 3.06 is vulnerable to Buffer Overflow via exif.c in function Put16u.

  • High 7.5
    CVE-2022-3602 Public exploit EPSS 91%

    X.509 Email Address 4-byte Buffer Overflow

    A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed the malicious certificate or for the ap…

  • High 7.5
    CVE-2022-3786 Public exploit EPSS 92%

    X.509 Email Address Variable Length Buffer Overflow

    A buffer overrun can be triggered in X.509 certificate verification, specifically in name constraint checking. Note that this occurs after certificate chain signature verification and requires either a CA to have signed a malicious certificate or for an appli…

  • High 7.8

    Oracle Solaris version 10 1/13, when using the Common Desktop Environment (CDE), is vulnerable to a privilege escalatio…

  • High 7.5

    IP-COM EW9 V15.11.0.14(9732) was discovered to contain a buffer overflow in the formSetDebugCfg function. This vulnerab…

  • High 7.3
  • High 7.8

    Memory corruption in Qualcomm IPC due to buffer copy without checking the size of input while starting communication wi…

  • High 7.5

    Tenda AC1200 US_AC6V2.0RTL_V15.03.06.51_multi_TDE01 was discovered to contain a buffer overflow in the 0x47de1c functio…

  • High 7.5

    Tenda AC1200 US_AC6V2.0RTL_V15.03.06.51_multi_TDE01 was discovered to contain a buffer overflow in the 0x475dc function…

  • High 7.5

    Tenda AC1900 AP500(US)_V1_180320(Beta) was discovered to contain a buffer overflow in the 0x32384 function. This vulner…

  • High 7.5

    Tenda AC1200 US_AC6V2.0RTL_V15.03.06.51_multi_TDE01 was discovered to contain a buffer overflow in the 0x47ce00 functio…

  • High 7.5

    Tenda AC1200 US_AC6V2.0RTL_V15.03.06.51_multi_TDE01 was discovered to contain a buffer overflow in the 0x47c5dc functio…

  • High 7.5

    Tenda AC1200 US_AC6V2.0RTL_V15.03.06.51_multi_TDE01 was discovered to contain a buffer overflow in the 0x4a12cc functio…

  • High 7.5

    Buffer overflow in pjlib scanner and pjmedia

    PJSIP is a free and open source multimedia communication library written in C. In versions of PJSIP prior to 2.13 the PJSIP parser, PJMEDIA RTP decoder, and PJMEDIA SDP parser are affeced by a buffer overflow vulnerability. Users connecting to untrusted clien…

  • High 7.5

    Buffer Overflow in `ProcessRadioRxDone` in LoRaMac-node

    LoRaMac-node is a reference implementation and documentation of a LoRa network node. Versions of LoRaMac-node prior to 4.7.0 are vulnerable to a buffer overflow. Improper size validation of the incoming radio frames can lead to an 65280-byte out-of-bounds wri…

  • High 7.4

    Cisco Catalyst 9100 Series Access Points Association Request Denial of Service Vulnerability

    A vulnerability in the 802.11 association frame validation of Cisco Catalyst 9100 Series Access Points (APs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to ins…

  • High 8.2

    SMM memory corruption vulnerability in OverClockSmiHandler SMM driver

    An attacker can exploit this vulnerability to elevate privileges from ring 0 to ring -2, execute arbitrary code in System Management Mode - an environment more privileged than operating system (OS) and completely isolated from it. Running arbitrary code in SM…

  • High 7.5

    D-Link DIR-1960 firmware DIR-1960_A1_1.11 was discovered to contain a buffer overflow via srtcat in prog.cgi. This vuln…

  • High 8.8

    A buffer overflow vulnerability exists in the confsrv ucloud_set_node_location functionality of TCL LinkHub Mesh Wi-Fi …

  • High 8.1

    Unverified DIO prefix info lengths in RPL-Classic in Contiki-NG

    Contiki-NG is an open-source, cross-platform operating system for IoT devices. In the RPL-Classic routing protocol implementation in the Contiki-NG operating system, an incoming DODAG Information Option (DIO) control message can contain a prefix information o…

  • High 8.1

    Buffer overflow in contiki-ng

    Contiki-NG is an open-source, cross-platform operating system for IoT devices. In affected versions it is possible to cause a buffer overflow when copying an IPv6 address prefix in the RPL-Classic implementation in Contiki-NG. In order to trigger the vulnerab…

  • High 8.4

    AES Crypt for Linux Password Security Vulnerability

    AES Crypt is a file encryption software for multiple platforms. AES Crypt for Linux built using the source on GitHub and having the version number 3.11 has a vulnerability with respect to reading user-provided passwords and confirmations via command-line prom…

  • High 7.3

    Buffer copy without checking size of input ('Classic Buffer Overflow') vulnerability in cgi component in Synology Audio…

  • High 7.5

    Junos OS: SRX series: The PFE will crash when specific traffic is scanned by Enhanced Web Filtering safe-search

    A Buffer Overflow vulnerability in the PFE of Juniper Networks Junos OS on SRX series allows an unauthenticated network based attacker to cause a Denial of Service (DoS). The PFE will crash when specific traffic is scanned by Enhanced Web Filtering safe-searc…

  • High 8.2

    This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop 16.5.1 …

  • High 8.8

    A CWE-120: Buffer Copy without Checking Size of Input vulnerability exists that could result in remote code execution o…

  • High 8.2

    A vulnerability has been identified in SCALANCE X200-4P IRT (All versions < V5.5.2), SCALANCE X201-3P IRT (All versions…

  • High 7.5
    CVE-2022-31626 Public exploit EPSS 58%

    mysqlnd/pdo password buffer overflow

    In PHP versions 7.4.x below 7.4.30, 8.0.x below 8.0.20, and 8.1.x below 8.1.7, when pdo_mysql extension with mysqlnd driver, if the third party is allowed to supply host to connect to and the password for the connection, password of excessive length can trigg…

  • High 7.5

    DoS Vulnerability in URLEncodedFormDecoder in Vapor

    Vapor is a server-side Swift HTTP web framework. When using automatic content decoding an attacker can craft a request body that can make the server crash with the following request: `curl -d "array[_0][0][array][_0][0][array]$(for f in $(seq 1100); do echo -…

  • High 7.5

    Denial-of-Service via internal structure overflow

    An unauthenticated attacker can send a specially crafted unauthenticated HTTP request to the device that can overflow a buffer. This vulnerability impacts products based on HID Mercury Intelligent Controllers LP1501, LP1502, LP2500, LP4502, and EP4502 which c…

  • High 7.6

    A Buffer Overflow vulnerability in the RSTP server component of Eufy Indoor 2K Indoor Camera allows a local attacker to…

  • High 7.5

    Buffer over-flow in Pillow

    libImaging/TgaRleDecode.c in Pillow 9.1.0 has a heap buffer overflow in the processing of invalid TGA image files.