CWE-777 - Regular Expression without Anchors
- Abstraction:Variant
- Structure:Simple
- Status:Incomplete
- Release Date:2009-07-27
- Latest Modification Date:2023-06-29
Weakness Name
Regular Expression without Anchors
Description
The product uses a regular expression to perform neutralization, but the regular expression is not anchored and may allow malicious or malformed data to slip through.
When performing tasks such as validating against a set of allowed inputs (allowlist), data is examined and possibly modified to ensure that it is well-formed and adheres to a list of safe values. If the regular expression is not anchored, malicious or malformed data may be included before or after any string matching the regular expression. The type of malicious data that is allowed will depend on the context of the application and which anchors are omitted from the regular expression.
Common Consequences
Scope: Availability, Confidentiality, Access Control
Impact: Bypass Protection Mechanism
Notes: An unanchored regular expression in the context of an allowlist will possibly result in a protection mechanism failure, allowing malicious or malformed data to enter trusted regions of the program. The specific consequences will depend on what functionality the allowlist was protecting.
