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
27 results · Clear filters · Feed
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Medium 5.3CVE-2026-94545 Public exploit
Satori-generated SVG has improper escaping
Satori is a library to convert HTML and CSS to SVG. Starting in version 0.0.27 and prior to version 0.33.5, Satori does not properly escape certain values before including them in generated SVG output. This can allow crafted values to be interpreted as SVG ma…
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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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Medium 6.3CVE-2026-49844 Public exploit
Apache Log4j API: Improper serialization of non-finite floating-point values in MapMessage.asJson()
Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0. The fix for CVE-2026-…
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High 7.8
Cisco Catalyst SD-WAN Controller Authenticated Privilege Escalation Vulnerability
A vulnerability in the CLI of Cisco Catalyst SD-WAN Controller, formerly SD-WAN vSmart, Cisco Catalyst SD-WAN Manager, formerly SD-WAN vManage, and Cisco Catalyst SD-WAN Validator, formerly SD-WAN vBond, could allow an authenticated, local attacker to execute…
KEV Jun 9, 2026 -
Low 2.1CVE-2026-48598 Public exploit
CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injection
Improper Encoding or Escaping of Output vulnerability in elixir-tesla tesla allows multipart part header injection via unescaped Content-Disposition parameter values. Tesla.Multipart.part_headers_for_disposition/1 interpolates each disposition parameter as #{…
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Medium 4.6CVE-2026-33657 Public exploit
EspoCRM: Stored HTML injection in email notifications about stream notes via unescaped post field
EspoCRM is an open source customer relationship management application. Versions 9.3.3 and below have a stored HTML injection vulnerability that allows any authenticated user with standard (non-administrative) privileges to inject arbitrary HTML into system-g…
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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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High 8.6CVE-2025-66024 Public exploit
XWiki Blog Application home page vulnerable to Stored XSS via Post Title
The XWiki blog application allows users of the XWiki platform to create and manage blog posts. Versions starting with 9.15 and prior to 9.15.7 are vulnerable to Stored Cross-Site Scripting (XSS) via the Blog Post Title. The vulnerability arises because the po…
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High 8.1CVE-2026-25940 Public exploit
jsPDF's PDF Injection in AcroForm module allows Arbitrary JavaScript Execution (RadioButton.createOption and "AS" property)
jsPDF is a library to generate PDFs in JavaScript. Prior to 4.2.0, user control of properties and methods of the Acroform module allows users to inject arbitrary PDF objects, such as JavaScript actions. If given the possibility to pass unsanitized input to on…
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High 8.1CVE-2026-25755 Public exploit
jsPDF has PDF Object Injection via Unsanitized Input in addJS Method
jsPDF is a library to generate PDFs in JavaScript. Prior to 4.2.0, user control of the argument of the `addJS` method allows an attacker to inject arbitrary PDF objects into the generated document. By crafting a payload that escapes the JavaScript string deli…
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High 8.3CVE-2025-55903 Public exploit
A HTML injection vulnerability exists in Perfex CRM v3.3.1. The application fails to sanitize user input in the "Bill T…
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High 7.2
motionEye vulnerable to RCE via unsanitized motion config parameter
MotionEye v0.43.1b4 and before is vulnerable to OS Command Injection in configuration parameters such as image_file_name. Unsanitized user input is written to Motion configuration files, allowing remote authenticated attackers with admin access to achieve cod…
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Critical 9.8CVE-2025-31651 Public exploit
Apache Tomcat: Bypass of rules in Rewrite Valve
Improper Neutralization of Escape, Meta, or Control Sequences vulnerability in Apache Tomcat. For a subset of unlikely rewrite rule configurations, it was possible for a specially crafted request to bypass some rewrite rules. If those rewrite rules effectivel…
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Medium 5.3
Improper encoding or escaping of output vulnerability in the webapi component in Synology BeeStation OS (BSM) before 1.…
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Critical 9.8CVE-2024-10441 Public exploit
Improper encoding or escaping of output vulnerability in the system plugin daemon in Synology BeeStation OS (BSM) befor…
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High 7.5CVE-2024-52005 Public exploit
The sideband payload is passed unfiltered to the terminal in git
Git is a source code management tool. When cloning from a server (or fetching, or pushing), informational or error messages are transported from the remote Git process to the client via the so-called "sideband channel". These messages will be prefixed with "r…
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High 7.8CVE-2024-34739 Public exploit
In shouldRestrictOverlayActivities of UsbProfileGroupSettingsManager.java, there is a possible escape from SUW due to a…
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Medium 5.4
Exim through 4.97.1 misparses a multiline RFC 2231 header filename, and thus remote attackers can bypass a $mime_filena…
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Critical 9.1
Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path.
Improper escaping of output in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to map URLs to filesystem locations that are permitted to be served by the server but are not intentionally/directly reachable by any URL, resulting in code…
KEV May 1, 2025 -
High 8.1
Apache HTTP Server proxy encoding problem
Encoding problem in mod_proxy in Apache HTTP Server 2.4.59 and earlier allows request URLs with incorrect encoding to be sent to backend services, potentially bypassing authentication via crafted requests. Users are recommended to upgrade to version 2.4.60, w…
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Critical 9.4
Command injection via array-ish $command parameter of proc_open()
In PHP versions 8.1.* before 8.1.28, 8.2.* before 8.2.18, 8.3.* before 8.3.5, when using proc_open() command with array syntax, due to insufficient escaping, if the arguments of the executed command are controlled by a malicious user, the user can supply argu…
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High 8.2CVE-2023-45539 Public exploit
HAProxy before 2.8.2 accepts # as part of the URI component, which might allow remote attackers to obtain sensitive inf…
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Medium 4.9CVE-2023-5968 Public exploit
Password hash in response body after username update
Mattermost fails to properly sanitize the user object when updating the username, resulting in the password hash being included in the response body.
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High 8.1CVE-2022-4137 Public exploit
Keycloak: reflected xss attack
A reflected cross-site scripting (XSS) vulnerability was found in the 'oob' OAuth endpoint due to incorrect null-byte handling. This issue allows a malicious link to insert an arbitrary URI into a Keycloak error page. This flaw requires a user or administrato…
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High 7.5
Shell command injection in gitea
Gitea before 1.16.7 does not escape git fetch remote.
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Critical 9.8CVE-2022-25235 Public exploit
xmltok_impl.c in Expat (aka libexpat) before 2.4.5 lacks certain validation of encoding, such as checks for whether a U…
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High 7.5CVE-2020-13654 Public exploit
Improper escaping in XWiki Platform
XWiki Platform before 12.8 mishandles escaping in the property displayer.