Weakness (CWE)
CWE-116: Improper Encoding or Escaping of Output
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
How to prevent it (7 mitigations)
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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.
For example, consider using the ESAPI Encoding control [REF-45] or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error.
Alternately, use built-in functions, but consider using wrappers in case those functions are discovered to have a vulnerability.
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Architecture and Design
If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.
For example, stored procedures can enforce database query structure and reduce the likelihood of SQL injection.
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Architecture and Design, Implementation
Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies.
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Architecture and Design
In some cases, input validation may be an important strategy when output encoding is not a complete solution. For example, you may be providing the same output that will be processed by multiple consumers that use different encodings or representations. In other cases, you may be required to allow user-supplied input to contain control information, such as limited HTML tags that support formatting in a wiki or bulletin board. When this type of requirement must be met, use an extremely strict allowlist to limit which control sequences can be used. Verify that the resulting syntactic structure is what you expect. Use your normal encoding methods for the remainder of the input.
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Architecture and Design
Use input validation as a defense-in-depth measure to reduce the likelihood of output encoding errors (see CWE-20).
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Requirements
Fully specify which encodings are required by components that will be communicating with each other.
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Implementation
When exchanging data between components, ensure that both components are using the same character encoding. Ensure that the proper encoding is applied at each interface. Explicitly set the encoding you are using whenever the protocol allows you to do so.
Source: MITRE CWE-116
77 results · Clear filters · Feed
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Critical 9.3
Stored XSS in @waline/client via the unsanitized markdown preview of a comment's raw body on edit
Waline is a comment system with backend support. In versions 3.15.2 and prior, @waline/client renders the comment editor's live preview with marked and no sanitizer (utils/markdown.ts), and the preview is injected with v-html. When a comment is edited, the ed…
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Critical 9.4
JupyterLab Desktop: Cross-Site Scripting (XSS) leading to Remote Code Execution on Connect URL
JupyterLab Desktop is the cross-platform desktop application for JupyterLab. Prior to 4.6.2-1, remote-server URLs were inserted into the server-selection dialog and Welcome view without safe encoding. An attacker who convinces a user to submit a crafted URL c…
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Critical 9.8
CGI versions before 5.00 for Perl allow Content-Disposition parameter injection via unescaped double quotes in the header attachment filename
CGI versions before 5.00 for Perl allow Content-Disposition parameter injection via unescaped double quotes in the header attachment filename. header(-attachment => $name) writes $name into the quoted filename parameter of Content-Disposition without escaping…
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Critical 9.1
CGI::Cookie versions before 5.00 for Perl allow cookie attribute injection via unvalidated path, domain and expires values
CGI::Cookie versions before 5.00 for Perl allow cookie attribute injection via unvalidated path, domain and expires values. The path, domain and expires values are written into the Set-Cookie header without checking for semicolons or control characters. An ap…
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Critical 9.3
fastapi-code-generator: Import-time RCE via route path -> unescaped @app.get('...') decorator
fastapi-code-generator creates FastAPI applications from OpenAPI files. Prior to 0.8.1, the generator inserts an OpenAPI path into a generated @app.get(...) route decorator as a single-quoted generated route string without escaping embedded quotes. An attacke…
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Critical 9.3
fastapi-code-generator: Import-time RCE via response status-code key -> unescaped @app.get(..., responses={...}) dict
fastapi-code-generator creates FastAPI applications from OpenAPI files. Prior to 0.8.1, the generator inserts an additional response status-code key into the generated responses={...} route-decorator dictionary as a single-quoted Python string without escapin…
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Critical 9.3
fastapi-code-generator: Call-time RCE via operation summary -> unescaped route-handler docstring
fastapi-code-generator creates FastAPI applications from OpenAPI files. Prior to 0.8.1, the generator inserts Operation.summary into a generated route-handler docstring as a triple-double-quoted string without escaping embedded triple quotes. An attacker-cont…
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Critical 9.8
Elo: Remote Code Execution in Elo Ruby backend via unescaped `#{...}` interpolation in emitted string literals and subtype-constraint labels
Elo is a purely functional expression language for no-code tools. Prior to 1.0.1, the Ruby backend in src/compilers/ruby.ts embeds attacker-controlled text in Ruby double-quoted strings without escaping #, so Ruby interpolation forms in the string-literal emi…
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Critical 9.1
Stanza injection in XMPP chat
Thunderbird did not escape attribute values when serializing outgoing XMPP stanzas. Because values from incoming requests were echoed back in automatic replies, a remote XMPP user could send a crafted request that caused Thunderbird to inject arbitrary stanza…
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Critical 9.8
Text::CSV_XS versions before 1.65 for Perl allow record splitting by writing strings used as numbers without quotes in combine
Text::CSV_XS versions before 1.65 for Perl allow record splitting by writing strings used as numbers without quotes in combine. combine and print do not check whether a field needs quotes when its value has Perl's integer or numeric flag set. Perl sets these …
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Critical 9.8
Text::CSV_XS versions before 1.65 for Perl drop the end of a record and its line ending when a UTF-8 flagged field precedes invalid UTF-8 bytes in print
Text::CSV_XS versions before 1.65 for Perl drop the end of a record and its line ending when a UTF-8 flagged field precedes invalid UTF-8 bytes in print. When a record contains a UTF-8 flagged field, print holds back trailing bytes that are not valid UTF-8 at…
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Critical 9.6
Improper Encoding or Escaping of Output in Crafty Controller
An output escaping vulnerability in the Audit Logs component of Crafty Controller allows a remote, unauthenticated attacker to perform stored cross-site scripting via HTTP header injection
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Critical 9.8
Vitess vttablet /twopcz reflected XSS
Vitess is a database clustering system for horizontal scaling of MySQL. Prior to 23.0.5 and 24.0.2, twopczHandler in go/vt/vttablet/tabletserver/twopcz.go writes the Action and dtid form values from the vttablet and vtcombo /twopcz HTTP debug endpoint into a …
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Critical 9.3
Contao: Cross-site scripting in the comments bundle
Contao is an Open Source CMS. From version 4.0.0 until 5.3.50 and 5.7.12, an unauthenticated visitor can submit a comment whose email or website metadata is rendered without sufficient attribute and URL encoding by listComments() in comments-bundle/contao/dca…
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Critical 10.0
Quasar Framework: Stored/Reflected XSS via unescaped SSR meta tag rendering in getHead()
Quasar Framework is a framework for building high-performance Vue.js user interfaces. Prior to 2.22.0, the SSR-only getHead() serializer in ui/src/plugins/meta/Meta.js used getAttr() to interpolate values supplied through useMeta() into title, meta, link, and…
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Critical 9.8CVE-2026-13684 Public exploit
An improper encoding or escaping of output vulnerability in SCGI in Synology DiskStation Manager (DSM) before 7.2.1-690…
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Critical 9.8
Sentry Seer vulnerability allows attacker-controlled input to be executed in a privileged environment
Sentry Seer is vulnerable to a multi-stage trust-boundary violation that allows unauthenticated attacker-controlled telemetry to become code that is executed by an agent in a privileged automation environment. An external attacker can submit fabricated Sentry…
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Critical 9.6
NationalSecurityAgency/skills-service has Stored XSS via User Registration Enabling Admin Account Takeover
SkillTree is a micro-learning gamification platform. Prior to version 4.4.2, two independent code flaws combine into a single exploitable attack chain, with three distinct exploitation paths of escalating impact. `StringHighlighter.js` builds an HTML string b…
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Critical 9.1
Apache CloudStack: Cross-Site Scripting (XSS) Vulnerability in Instance Reset Password Function in UI
Improper Encoding or Escaping of Output vulnerability in Apache CloudStack's UI while using Instance Reset Password functionality. This issue affects Apache CloudStack: from 4.15.1.0 through 4.20.3.0 and from 4.21.0.0 through 4.22.1.0. Users are recommended t…
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Critical 9.3
Orval: RCE via servers[].url -> unescaped request-URL template literal (with getBaseUrlFromSpecification)
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, an unescaped backtick in servers[0].url is emitted into request URL template literals generated when output.baseUrl.getBaseUrlFromSpecif…
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Critical 9.3
Orval: Import-time RCE via schema default -> zod module-level template literal
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a ${...} expression or backtick in a schema default is emitted into a module-level template literal emitted by zod schema generation wit…
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Critical 9.3
Orval: Import-time RCE via query parameter name -> computed-property-key injection in the zod cli
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a double quote in a query parameter name is emitted into the generated request-validation zod.object({...}) schema without safe encoding…
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Critical 9.3
Orval: Import-time RCE via array-items default -> zod module-level template literal
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a ${...} expression or backtick in an array item default is emitted into a module-level template literal emitted by zod schema generatio…
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Critical 9.3
Orval: Import-time RCE via header parameter name -> computed-property-key injection in the zod client
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a double quote in a header parameter name is emitted into the generated request-validation zod.object({...}) schema without safe encodin…
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Critical 9.3
Orval: Import-time RCE via header-parameter default -> zod module-level template literal
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, a ${...} expression or backtick in a header parameter default is emitted into a module-level template literal emitted by zod schema gene…
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Critical 9.3
Orval: RCE via OpenAPI path -> unescaped request-URL template literal (backtick breakout)
Orval generates type-safe JavaScript clients in TypeScript from OpenAPI v3 and Swagger v2 specifications. Prior to 8.21.0, an unescaped backtick in an OpenAPI path is emitted into request URL template literals generated for axios, fetch, react-query, and SWR …
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Critical 9.1
An issue was discovered in openRISC OR1200 commit 83ac6b. An output mismatch between the RTL and the netlist of the or1…
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Critical 9.1
Adobe Commerce | Improper Encoding or Escaping of Output (CWE-116)
Adobe Commerce is affected by an Improper Encoding or Escaping of Output vulnerability that could result in arbitrary code execution in the context of the current user. An attacker with high privileges could exploit this vulnerability to execute arbitrary cod…
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Critical 9.0
SiYuan: Stored XSS results to Electron RCE in SiYuan marketplace via unescaped `data-obj` attribute (Bypass for CVE-2026-45375's patch)
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, it does not escape the untrusted fields (name, version, author, description) when they are serialized into the data-obj HTML attribute of each marketplace card. Because the attribu…
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Critical 9.3
pgAdmin 4: Stored XSS via untrusted error and plan-node text rendered through html-react-parser
Stored cross-site scripting in pgAdmin 4's error-rendering and plan-node-rendering paths. Text returned by a PostgreSQL server (ErrorResponse messages, including object names quoted back inside relation-does-not-exist errors and inside EXPLAIN Recheck Cond / …
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Critical 9.8
jmespath.php has CompilerRuntime code injection via unescaped function names
jmespath.php allows users to use JMESPath, software for declaratively specifying how to extract elements from a JSON document, in PHP applications with PHP data structures. Versions prior to 2.9.1 can generate and execute attacker-controlled PHP code when `Jm…
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Critical 9.3
HAX CMS: Stored XSS via '<video-player>' component allows arbitrary JavaScript execution and token theft
HAX CMS helps manage microsite universe with PHP or NodeJs backends. A stored cross-site scripting (XSS) vulnerability exists in versions prior to 26.0.0 due to improper sanitization of the `<video-player>` component. The component allows `javascript:` URIs i…
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Critical 9.4
SiYuan: URL-encoded title bypasses `escapeAriaLabel`, decoded by `decodeURIComponent` into a tooltip-XSS
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, he tooltip mouseover handler in app/src/block/popover.ts reads aria-label via getAttribute and passes it through decodeURIComponent before assigning to messageElement.innerHTML in …
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Critical 9.0
SiYuan: Bazaar marketplace renders unescaped package `name` and `version` metadata, allowing stored XSS and Electron code execution
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, SiYuan's Bazaar (community marketplace) renders the name and version fields of a package's plugin.json (and the equivalent theme.json / template.json / widget.json / icon.json) int…
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Critical 9.9
Apache Polaris: could broaden vended S3 credentials through wildcard-bearing namespace or table names
Apache Polaris accepts literal `*` characters in namespace and table names. When it later builds temporary S3 access policies for delegated table access, those same characters appear to be reused unescaped in S3 IAM resource patterns and `s3:prefix` condition…
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Critical 9.4
OpenBao has Reflected XSS in its OIDC authentication error message
OpenBao is an open source identity-based secrets management system. Prior to version 2.5.2, OpenBao installations that have an OIDC/JWT authentication method enabled and a role with `callback_mode=direct` configured are vulnerable to XSS via the `error_descri…
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Critical 9.3CVE-2026-32913 Public exploit
OpenClaw < 2026.3.7 - Custom Authorization Header Leakage via Cross-Origin Redirects
OpenClaw before 2026.3.7 contains an improper header validation vulnerability in fetchWithSsrFGuard that forwards custom authorization headers across cross-origin redirects. Attackers can trigger redirects to different origins to intercept sensitive headers l…
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Critical 9.3
FreeScout: Stored XSS via Unescaped Email Template Rendering ({!! $thread->body !!})
FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Versions 1.8.208 and below are vulnerable to Stored Cross-Site Scripting (XSS) through FreeScout's email notification templates. Incoming email bodies are stored in the databas…
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Critical 9.7
5ire vulnerable to Remote Code Execution (RCE)
5ire is a cross-platform desktop artificial intelligence assistant and model context protocol client. Prior to version 0.15.3, an unsafe HTML rendering permits untrusted HTML (including on* event attributes) to execute in the renderer context. An attacker can…
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Critical 9.4
Coolify has Stored XSS in Project Name
Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Coolify versions prior to and including v4.0.0-beta.420.6 are vulnerable to a stored cross-site scripting (XSS) attack in the project creation workflow. An aut…