No Duplicate Attributes
ID |
html.attr_no_duplication |
Severity |
high |
Remediation Complexity |
trivial |
Remediation Risk |
low |
Remediation Effort |
low |
Resource |
Reliability |
Language |
Html |
Tags |
reliability |
Description
Flags an opening element that declares the same attribute name twice or more. The comparison is case-insensitive on the attribute short name.
Rationale
Duplicate attributes are a parse error in HTML. The browser keeps only the first occurrence and silently drops the rest, so the markup does not behave as written. The duplication is almost always a copy-paste mistake that masks the author’s real intent.
<input type="text" type="password"> <!-- FLAW — type declared twice, stays a text field -->
<input type="password" name="pwd"> <!-- OK — each attribute declared once -->Remediation
Remove the redundant attribute and keep the single occurrence that carries the intended value.