CWE-777 1 CVEs MITRE definition ↗

CWE-777: Regular Expression without Anchors

Overview

CWE-777 (Regular Expression without Anchors) documents a weakness type used across vulnerability databases and security assessments. Use the sections below for definition, context, and mapped CVEs.

Security impact
Security impact: Depends on product and context; use CVE records, severity scores, and MITRE guidance to prioritize.

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.

Background details

Extended context from the CWE catalog (rendered from MITRE XHTML).

Regular expressions are typically used to match a pattern of text. Anchors are used in regular expressions to specify where the pattern should match: at the beginning, the end, or both (the whole input).

Applicable platforms

Kind Name Class Prevalence OS / CPE
language Not Language-Specific Undetermined
technology Not Technology-Specific Undetermined

Related CVEs in this database

These CVEs are mapped to this weakness in this database and kept for traceability and search.

CVE Published Summary
CVE-2026-40110 2026-05-05 Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the Origin header validation uses Python's re.match() to check incoming origins against the allow_origin_pat…

Content submission

Name
CWE Content Team
Organization
MITRE
Date
2009-06-30
Version
1.5

Content modifications

Date Name Version Importance Comment
2010-06-21 CWE Content Team 1.9 updated Description
2011-06-01 CWE Content Team 1.13 updated Common_Consequences
2017-11-08 CWE Content Team 3.0 updated Likelihood_of_Exploit
2020-02-24 CWE Content Team 4.0 updated Relationships
2020-06-25 CWE Content Team 4.1 updated Common_Consequences, Description, Potential_Mitigations
2022-10-13 CWE Content Team 4.9 updated Demonstrative_Examples, Observed_Examples
2023-01-31 CWE Content Team 4.10 updated Description
2023-04-27 CWE Content Team 4.11 updated Relationships
2023-06-29 CWE Content Team 4.12 updated Mapping_Notes
2025-12-11 CWE Content Team 4.19 updated Applicable_Platforms, Weakness_Ordinalities
cvelogic Threat Intelligence