CWE-86—Improper Neutralization of Invalid Characters in Identifiers in Web Pages

Weakness Name

Improper Neutralization of Invalid Characters in Identifiers in Web Pages

Description

The product does not neutralize or incorrectly neutralizes invalid characters or byte sequences in the middle of tag names, URI schemes, and other identifiers.

Some web browsers may remove these sequences, resulting in output that may have unintended control implications. For example, the product may attempt to remove a "javascript:" URI scheme, but a "java%00script:" URI may bypass this check and still be rendered as active javascript by some browsers, allowing XSS or other attacks.

Common Consequences

Scope:

Confidentiality, Integrity, Availability

Impact:

Read Application Data, Execute Unauthorized Code or Commands

Related Weaknesses

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')High
• CWE-184Incomplete List of Disallowed Inputs
• CWE-436Interpretation Conflict