The web application improperly neutralizes user-controlled input for executable script disguised with URI encodings.
View on MITREResolve all URIs to absolute or canonical representations before processing.
Carefully check each input parameter against a rigorous positive specification (allowlist) defining the specific characters and format allowed. All input should be neutralized, not just parameters that the user is supposed to specify, but all data in the request, including tag attributes, hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. We often encounter data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended.
No detection method information available for this CWE.
Cross-site scripting (XSS) vulnerability in Novell Groupwise WebAccess 6.5 before July 11, 2005 allows remote attackers to inject arbitrary web script or HTML via an e-mail message with an encoded javascript URI (e.g. "jAvascript" in an IMG tag).
View DetailsNo relationship information available for this CWE.
CWE-84: Improper Neutralization of Encoded URI Schemes in a Web Page is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The web application improperly neutralizes user-controlled input for executable script disguised with URI encodings.
If exploited, CWE-84 (Improper Neutralization of Encoded URI Schemes in a Web Page) it can compromise Integrity, leading to outcomes such as Unexpected State.
Recommended mitigations for CWE-84 include: Resolve all URIs to absolute or canonical representations before processing. Carefully check each input parameter against a rigorous positive specification (allowlist) defining the specific characters and format allowed. All input should be neutralized, not just parameters that the user is supposed to specify, but all data in the request, including tag attributes, hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. We often encounter data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended.
CWE-84 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.
MITRE documents real CVEs mapped to CWE-84, including CVE-2005-2276, CVE-2005-0692, CVE-2002-0117 and CVE-2002-0118. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.
A CWE (Common Weakness Enumeration) like CWE-84 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.