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
2,644 results · Clear filters · Feed
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High 7.5
Maximo AI Service Improper Input Validation
IBM Maximo AI Service 9.1.0, and 9.2.0 could allow a remote attacker to cause a denial of service due to improper input validation.
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High 8.8
Nginx UI: MCP nginx_config_add skips config directive validation → authenticated nginx directive injection (RCE on the official image)
Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, internal/config/validation.go (ValidateConfigFile) is a security control that blocks dangerous nginx directives — js_*, perl_*, load_module of the njs/perl modules, and user root. It i…
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High 8.8
PraisonAI: Server-Side Request Forgery (SSRF) in SearxNG / search_web tools via attacker-controlled searxng_url parameter
PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.62, searxng_search and the search_web SearxNG provider pass the LLM-controlled searxng_url parameter directly to requests.get without validating its scheme, host, port, or resolved address.…
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High 8.6
Improper input validation in parsing sheifd in libsimba.heifdec.media.samsung.so prior to SMR Oct-2026 Release 1 allows…
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High 8.6
Improper input validation in getting cover image in libsimba.heifdec.media.samsung.so prior to SMR Oct-2026 Release 1 a…
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High 8.8
Apache Camel Karavan: unvalidated Kubernetes resources applied from a project's kubernetes.yaml
Improper input validation vulnerability in Apache Camel Karavan. When a deployment was started, Karavan unmarshalled a project's `kubernetes.yaml` and applied every resource it contained to the cluster without restricting the resource kinds, without rejecting…
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High 7.1
SumatraPDF: SyncTeX Argument Injection in Inverse Search Enables Arbitrary Command Execution via External Editors
SumatraPDF is a multi-format reader for Windows. In 3.5.2 and earlier, an attacker-controlled SyncTeX source filename is substituted for the %f placeholder in an external editor command line without safe Windows argument quoting, and the resulting command lin…
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High 7.4CVE-2026-107720 Public exploit
fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set
fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.3.1, fast-jwt createVerifier accepts an unsigned JWT when key is an empty string or null and algorithms is a non-empty allowlist. Falsy synchronous keys bypass prepareKeyOrSecret, allowedA…
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High 8.2
Cisco Meraki Hardening Release - Input Validation Vulnerabilities
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco networking engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple interna…
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High 8.6
Cisco NX-OS Software Security Hardening Release: October 2026 - Improper Input Validation Vulnerabilities
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco NX-OS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally d…
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High 8.8
WeasyPrint: EPS images reach the Ghostscript interpreter resulting in RCE
WeasyPrint helps web developers to create PDF documents. Prior to 70.0, the image-loading path in weasyprint/images.py passes fetched image bytes from HTML img URLs, CSS image values, SVG image references, and data URIs to Pillow's generic image dispatcher wi…
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High 8.4
MISP sachertortephp - CakeResponse::download() HTTP Response Splitting via Unsanitized Filename Enables Stored XSS
The CakeResponse::download() method in lib/Cake/Network/CakeResponse.php constructs a Content-Disposition header by directly interpolating a caller-supplied filename into a quoted-string value without sanitization. Two distinct injection vectors exist in the …
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High 7.8
In checkCallerIsCertInstallerOrSelfInProfile of CredentialStorageActivity.java, there is a possible permission bypass d…
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High 7.8
In FilterCapturedPacket of snoop_logger.cc, there is a possible memory safety issue due to improper input validation. T…
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High 8.8
Hypershift: hypershift: unsanitized kubeconfig passthrough from tenant namespace to control plane
A flaw was found in the HyperShift operator. The operator copies user-provided Kubernetes configuration (kubeconfig) secrets directly into the privileged control plane namespace without proper validation or sanitization. An authenticated user with cluster and…
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High 8.4
Mitel MiVoice Office 400 Music on Hold WAV File Upload Code Execution
DigitalCanion SA has discovered a vulnerability that allows remote attackers to execute arbitrary code on affected installations of the product. Authentication may be required to exploit this vulnerability. The specific flaw exists within the Configuration → …
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High 8.7
Taskcluster: Unauthenticated remote code execution in `web-server` via GraphQL `filter` argument (sift `$where`)
Taskcluster is the task execution framework that supports Mozilla's continuous integration and release processes. Prior to version 100.3.0, Taskcluster is vulnerable to unauthenticated RCE on Taskcluster deployments with an anonymous role that exposes the Gra…
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High 8.3
MISP Stored Cross-Site Scripting (XSS) via Unvalidated Event Graph Preview Image
MISP contains a stored cross-site script (XSS) vulnerability in the event graph preview feature. The event graph preview image field was accepted and stored without server-side validation. On the client side, the stored value was rendered into an HTML img ele…
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High 7.5
Apache WSS4J: Insufficient Validation of Derived-Key Parameters
Apache WSS4J accepted attacker-controlled derived-key lengths and offsets without adequate bounds. This could permit cryptographically weak keys or excessive CPU and memory consumption when processing crafted WS-Security messages. The fixes enforce a minimum …
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High 8.3
MISP: Nested Model Alias Key Bypasses Sanitization to Modify Cross-Tenant Rows
MISP contains an improper input validation vulnerability in its ORM save path. When a user submits data through various endpoints (attribute add/edit, event edit, free-text import, sighting capture, shadow attribute proposal, event report creation, object ref…
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High 7.5
russh: Client-side channel-scoped Handler callbacks fire for channel IDs the client never opened
Russh is a Rust SSH client and server library. Prior to 0.63.1, client_read_authenticated in russh/src/client/encrypted.rs forwards CHANNEL_DATA, CHANNEL_EXTENDED_DATA, CHANNEL_EOF, CHANNEL_CLOSE, CHANNEL_OPEN_FAILURE, CHANNEL_SUCCESS, CHANNEL_FAILURE, and CH…
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High 7.8
Electron: Sandboxed preload code cache can be poisoned by a compromised renderer
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. From 42.3.3 until 42.10.0, 43.5.0, and 44.0.0-beta.6, Electron's sandboxed preload code cache did not verify that a cached entry matched the preload it was…
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High 8.3
Improper input validation in Desktop in Google Chrome prior to 154.0.8037.57 allowed a remote attacker who had compromi…
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High 8.3
Improper input validation in Themes in Google Chrome prior to 154.0.8037.57 allowed a remote attacker who had compromis…
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High 8.3
Improper input validation in Printing in Google Chrome prior to 154.0.8037.57 allowed a remote attacker who had comprom…
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High 7.5
Socket.IO: Prototype Pollution via Unsafe Client Session Lookup
Socket.IO enables bidirectional and low-latency communication for every platform. Prior to 0.1.1, @socket.io/cluster-engine uses inherited object properties when looking up attacker-controlled session IDs in clustered deployments. Special property names such …
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High 8.6
FreePBX: Authenticated Superfecta Arbitrary PHP Code Execution (RCE via Unsafe File Inclusion)
FreePBX is an open source IP PBX. Prior to versions 16.0.40 and 17.0.7, a critical remote code execution (RCE) vulnerability exists in the superfecta module due to unsafe inclusion of arbitrary PHP files, allowing authenticated attackers to execute arbitrary …
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High 7.2
Authenticated PowerShell Injection in DNS Query Resolution Policy leads to RCE
ManageEngine DDI Central versions below 6201 are vulnerable to Command injection in Windows DNS Query Resolution Policy name field leading to remote code execution.
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High 8.8
Authenticated PowerShell Injection leads to RCE
ManageEngine DDI Central versions below 6201 are vulnerable to PowerShell command injection in Windows DNS SPF/TXT record push leading to remote code execution.
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High 7.3
Trusted Domain Project OpenDMARC policy.c improper validation of unsafe equivalence in input
A flaw has been found in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this issue is some unknown functionality of the file policy.c of the component Domain Handler. Executing a manipulation can lead to improper validation of unsafe equivalence in…
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High 7.3
OctoberCMS ResizeImages.php getSourcePathForResize server-side request forgery
A vulnerability was found in OctoberCMS up to 4.1.19/4.2.25/4.3.4. The impacted element is the function getSourcePathForResize of the file modules/system/classes/ResizeImages.php. The manipulation of the argument realSourcePath results in server-side request …
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High 7.0CVE-2026-88774 Public exploit
Feature policy bypass due to improper HTTP URL based expression usage
Vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to a feat…
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High 7.5
Netty 4.2.2 through 4.2.17 HTTP/1 Host Header Authority Confusion
Netty's HTTP/3 codec (io.netty:netty-codec-http3) versions 4.2.2.Final through 4.2.17.Final builds the HTTP/3 :authority pseudo-header from the HTTP/1 Host header before considering the authority of an absolute-form HTTP/1 request-target. In HttpConversionUti…
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High 7.5
Netty HTTP/1 CONNECT authority-form mistranslated to malformed HTTP/3
Netty's HTTP/3 codec (io.netty:netty-codec-http3) from 4.2.2.Final through 4.2.17.Final does not special-case HTTP/1 CONNECT authority-form request-targets when converting HTTP/1 messages to HTTP/3 in HttpConversionUtil.toHttp3Headers. The authority-form targ…
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High 8.6
Zammad: AI Agent template sanitizer bypass leads to remote code execution
Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, a security filter that protects Zammad's AI Agent configuration can be bypassed by entering specially crafted text into one of an AI Agent's fields. An administrator with perm…
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High 8.8
Malicious user input may lead to RCE in golang.org/x/playground
A malicious txtar could escape the intended execution context and force arbitrary writes to the playground host's trusted filesystem. Disjointly, one of the three possible paths to invoke go vet on the playground host did not correctly restrict the execution …
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High 7.2
Piwigo arbitrary file read and remote code execution via insecure image processing
Piwigo before v16.4.0 is vulnerable to arbitrary file read and remote code execution in image upload handling when using the Imagick library due to insufficient validation and unsafe processing of user-supplied image files. By abusing format confusion (e.g., …
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High 7.3
Open-Web-Analytics Remote Event Queue Endpoint queue.php loadFromArray deserialization
A security flaw has been discovered in Open-Web-Analytics up to 1.8.1. Affected is the function Event::loadFromArray of the file queue.php of the component Remote Event Queue Endpoint. Performing a manipulation results in deserialization. The attack can be in…
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High 7.3
halo-dev Halo SpEL ReplyNotificationSubscriptionHelper.java neutralization
A security vulnerability has been detected in halo-dev Halo up to 2.25.4/2.26.1. Affected is an unknown function of the file application/src/main/java/run/halo/app/content/comment/ReplyNotificationSubscriptionHelper.java of the component SpEL Handler. Such ma…
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High 8.8
An issue in geelen mcp-remote 0.1.16 through 0.1.38 allows a remote attacker to execute arbitrary code via the open() f…