Weakness (CWE)
CWE-20: Improper Input Validation
The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.
How to prevent it (8 mitigations)
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Architecture and Design
Consider using language-theoretic security (LangSec) techniques that characterize inputs using a formal language and build "recognizers" for that language. This effectively requires parsing to be a distinct layer that effectively enforces a boundary between raw input and internal data representations, instead of allowing parser code to be scattered throughout the program, where it could be subject to errors or inconsistencies that create weaknesses. [REF-1109] [REF-1110] [REF-1111]
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Architecture and Design
Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
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Architecture and Design, Implementation
Understand all the potential areas where untrusted inputs can enter the product, including but not limited to: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
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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.
Even though client-side checks provide minimal benefits with respect to server-side security, they are still useful. First, they can support intrusion detection. If the server receives input that should have been rejected by the client, then it may be an indication of an attack. Second, client-side error-checking can provide helpful feedback to the user about the expectations for valid input. Third, there may be a reduction in server-side processing time for accidental input errors, although this is typically a small savings.
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Implementation
When your application combines data from multiple sources, perform the validation after the sources have been combined. The individual data elements may pass the validation step but violate the intended restrictions after they have been combined.
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Implementation
Be especially careful to validate all input when invoking code that crosses language boundaries, such as from an interpreted language to native code. This could create an unexpected interaction between the language boundaries. Ensure that you are not violating any of the expectations of the language with which you are interfacing. For example, even though Java may not be susceptible to buffer overflows, providing a large argument in a call to native code might trigger an overflow.
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Implementation
Directly convert your input type into the expected data type, such as using a conversion function that translates a string into a number. After converting to the expected data type, ensure that the input's values fall within the expected range of allowable values and that multi-field consistencies are maintained.
Source: MITRE CWE-20
368 results · Clear filters · Feed
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High 7.8
In binder_transaction of binder.c, there is a possible out of bounds write due to an incorrect bounds check. This could…
KEV Nov 3, 2021 -
Critical 9.8
JGit Improper Input Validation vulnerability
Git before 1.8.5.6, 1.9.x before 1.9.5, 2.0.x before 2.0.5, 2.1.x before 2.1.4, and 2.2.x before 2.2.1 on Windows and OS X; Mercurial before 3.2.3 on Windows and OS X; Apple Xcode before 6.2 beta 3; mine all versions before 08-12-2014; libgit2 all versions up…
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High 7.5
Improper Input Validation in Apache Solr
Apache Solr 5.0.0 to Apache Solr 8.3.1 are vulnerable to a Remote Code Execution through the VelocityResponseWriter. A Velocity template can be provided through Velocity templates in a configset `velocity/` directory or as a parameter. A user defined configse…
KEV Nov 3, 2021 -
High 7.7
Cisco Wireless LAN Controller HTTP Parsing Engine Denial of Service Vulnerability
A vulnerability in the web interface of Cisco Wireless LAN Controller Software could allow a low-privileged, authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists due to a failure of the HT…
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High 7.2
Improper Input Validation in Centreon Web
Centreon Web before 2.8.30, 18.10.x before 18.10.8, 19.04.x before 19.04.5 and 19.10.x before 19.10.2 allows Remote Code Execution by an administrator who can modify Macro Expression location settings. CVE-2019-16405 and CVE-2019-17501 are similar to one anot…
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Unscored —
Moxa EDR 810, all versions 5.1 and prior, allows an authenticated attacker to abuse the ping feature to execute unautho…
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High 7.2
Cisco Integrated Management Controller Supervisor, Cisco UCS Director, and Cisco UCS Director Express for Big Data Command Injection Vulnerability
A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Supervisor, Cisco UCS Director, and Cisco UCS Director Express for Big Data could allow an authenticated, remote attacker to execute arbitrary commands on th…
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High 7.2
Cisco Small Business 220 Series Smart Switches Command Injection Vulnerability
A vulnerability in the web management interface of Cisco Small Business 220 Series Smart Switches could allow an authenticated, remote attacker to perform a command injection attack. The vulnerability is due to insufficient validation of user-supplied input. …
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Critical 9.1CVE-2019-10744 Public exploit
Prototype Pollution in lodash
Versions of lodash lower than 4.17.12 are vulnerable to Prototype Pollution. The function defaultsDeep could be tricked into adding or modifying properties of Object.prototype using a constructor payload.
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Critical 10.0
Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can resul…
KEV May 23, 2022 -
High 8.8
A remote code execution vulnerability exists in Microsoft SQL Server when it incorrectly handles processing of internal…
KEV Aug 26, 2026 -
High 8.8
Cisco Prime Infrastructure and Evolved Programmable Network Manager Remote Code Execution Vulnerabilities
A vulnerability in the web-based management interface of Cisco Prime Infrastructure (PI) and Cisco Evolved Programmable Network (EPN) Manager could allow an authenticated, remote attacker to execute code with root-level privileges on the underlying operating …
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High 7.5CVE-2019-10742 Public exploit
Denial of Service in axios
Axios up to and including 0.18.0 allows attackers to cause a denial of service (application crash) by continuing to accepting content after maxContentLength is exceeded.
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High 7.8CVE-2019-11687 Public exploit
An issue was discovered in the DICOM Part 10 File Format in the NEMA DICOM Standard 1995 through 2019b and continuing i…
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High 7.4CVE-2019-1749 Public exploit
Cisco Aggregation Services Router 900 Route Switch Processor 3 OSPFv2 Denial of Service Vulnerability
A vulnerability in the ingress traffic validation of Cisco IOS XE Software for Cisco Aggregation Services Router (ASR) 900 Route Switch Processor 3 (RSP3) could allow an unauthenticated, adjacent attacker to trigger a reload of an affected device, resulting i…
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High 7.5CVE-2019-6690 Public exploit
Improper Input Validation python-gnupg
python-gnupg 0.4.3 allows context-dependent attackers to trick gnupg to decrypt other ciphertext than intended. To perform the attack, the passphrase to gnupg must be controlled by the adversary and the ciphertext should be trusted. Related to a "CWE-20: Impr…
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Critical 9.8
A remote code execution vulnerability exists in Microsoft SharePoint when the software fails to check the source markup…
KEV Nov 3, 2021 -
High 7.2
Cisco Small Business RV320 and RV325 Routers Command Injection Vulnerability
A vulnerability in the web-based management interface of Cisco Small Business RV320 and RV325 Dual Gigabit WAN VPN Routers could allow an authenticated, remote attacker with administrative privileges on an affected device to execute arbitrary commands. The vu…
KEV Mar 3, 2022 -
Critical 9.8
PHAR stream wrapper Arbitrary PHP code execution
In Drupal Core versions 7.x prior to 7.62, 8.6.x prior to 8.6.6 and 8.5.x prior to 8.5.9; A remote code execution vulnerability exists in PHP's built-in phar stream wrapper when performing file operations on an untrusted phar:// URI. Some Drupal code (core, c…
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Medium 5.9CVE-2018-16875 Public exploit
Denial of service in chain verification in crypto/x509
The crypto/x509 package of Go before 1.10.6 and 1.11.x before 1.11.3 does not limit the amount of work performed for each chain verification, which might allow attackers to craft pathological inputs leading to a CPU denial of service. Go TLS servers accepting…
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Critical 9.8
Improper Input Validation in alilibaba:fastjson
parseObject in Fastjson before 1.2.25, as used in FastjsonEngine in Pippo 1.11.0 and other products, allows remote attackers to execute arbitrary code via a crafted JSON request, as demonstrated by a crafted rmi:// URI in the dataSourceName field of HTTP POST…
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Unscored —CVE-2018-0438 Public exploit
Cisco Umbrella Enterprise Roaming Client Privilege Escalation Vulnerability
A vulnerability in the Cisco Umbrella Enterprise Roaming Client (ERC) could allow an authenticated, local attacker to elevate privileges to Administrator. To exploit the vulnerability, the attacker must authenticate with valid local user credentials. This vul…
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High 8.1
Apache Struts vulnerable to remote command execution (RCE) due to improper input validation
Apache Struts versions 2.3 to 2.3.34 and 2.5 to 2.5.16 suffer from possible Remote Code Execution when alwaysSelectFullNamespace is true (either by user or a plugin like Convention Plugin) and then: results are used with no namespace and in same time, its upp…
KEV Nov 3, 2021 -
High 8.8
A remote code execution vulnerability exists when the Windows Shell does not properly validate file paths, aka "Windows…
KEV Mar 25, 2022 -
High 7.5CVE-2018-10920 Public exploit
Improper input validation bug in DNS resolver component of Knot Resolver before 2.4.1 allows remote attacker to poison …
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High 7.5
Improper Input Validation in Jenkins
A arbitrary file read vulnerability exists in Jenkins 2.132 and earlier, 2.121.1 and earlier in the Stapler web framework's org/kohsuke/stapler/Stapler.java that allows attackers to send crafted HTTP requests returning the contents of any file on the Jenkins …
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Critical 9.8
Codiad remote code execution vulnerability
Codiad through 2.8.4 allows Remote Code Execution, a different vulnerability than CVE-2017-11366 and CVE-2017-15689.
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High —
High severity vulnerability that affects org.apache.cxf.fediz:fediz-jetty8, org.apache.cxf.fediz:fediz-jetty9, org.apache.cxf.fediz:fediz-spring, org.apache.cxf.fediz:fediz-spring2, and org.apache.cxf.fediz:fediz-spring3
Versions of Apache CXF Fediz prior to 1.4.4 do not fully disable Document Type Declarations (DTDs) when either parsing the Identity Provider response in the application plugins, or in the Identity Provider itself when parsing certain XML-based parameters.
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High 7.5
A vulnerability in the web interface of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, rem…
KEV Nov 3, 2021 -
Critical —CVE-2016-10555 Public exploit
Forgeable Public/Private Tokens in jwt-simple
Since "algorithm" isn't enforced in jwt.decode()in jwt-simple 0.3.0 and earlier, a malicious user could choose what algorithm is sent sent to the server. If the server is expecting RSA but is sent HMAC-SHA with RSA's public key, the server will think the publ…
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Critical —CVE-2015-9235 Public exploit
Verification Bypass in jsonwebtoken
In jsonwebtoken node module before 4.2.2 it is possible for an attacker to bypass verification when a token digitally signed with an asymmetric key (RS/ES family) of algorithms but instead the attacker send a token digitally signed with a symmetric algorithm …
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Medium 6.6
Ansible is vulnerable to an improper input validation in Ansible's handling of data sent from client systems
Ansible before versions 2.1.4, 2.2.1 is vulnerable to an improper input validation in Ansible's handling of data sent from client systems. An attacker with control over a client system being managed by Ansible and the ability to send facts back to the Ansible…
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Unscored —CVE-2018-0239 Public exploit
A vulnerability in the egress packet processing functionality of the Cisco StarOS operating system for Cisco Aggregatio…
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Critical 9.8
Spring Data Commons remote code injection vulnerability
Spring Data Commons, versions prior to 1.13 to 1.13.10, 2.0 to 2.0.5, and older unsupported versions, contain a property binder vulnerability caused by improper neutralization of special elements. An unauthenticated remote malicious user (or attacker) can sup…
KEV Mar 25, 2022 -
High 8.8
Improper Input Validation in Datomic
H2 1.4.197, as used in Datomic before 0.9.5697 and other products, allows remote code execution because CREATE ALIAS can execute arbitrary Java code. NOTE: the vendor's position is "h2 is not designed to be run outside of a secure environment."
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Critical 9.8
Drupal Core Remote Code Execution Vulnerability
Drupal before 7.58, 8.x before 8.3.9, 8.4.x before 8.4.6, and 8.5.x before 8.5.1 allows remote attackers to execute arbitrary code because of an issue affecting multiple subsystems with default or common module configurations.
KEV Nov 3, 2021 -
High 7.5
A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthentic…
KEV Nov 3, 2021 -
High 7.2
High severity vulnerability that affects org.apache.syncope:syncope-core
An administrator with report and template entitlements in Apache Syncope 1.2.x before 1.2.11, 2.0.x before 2.0.8, and unsupported releases 1.0.x and 1.1.x which may be also affected, can use XSL Transformations (XSLT) to perform malicious operations, includin…
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Unscored —
A flaw was found in the way Postgresql allowed a user to modify the behavior of a query for other users. An attacker wi…
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Medium 5.5CVE-2018-1047 Public exploit
Improper Input Validation in org.wildfly:wildfly-undertow
A flaw was found in Wildfly 9.x. A path traversal vulnerability through the org.wildfly.extension.undertow.deployment.ServletResourceManager.getResource method could lead to information disclosure of arbitrary local files.