The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as comment delimiters when they are sent to a downstream component.
View on MITREDevelopers should anticipate that comments will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected and appropriate input is processed by the system.
No detection method information available for this CWE.
Mail client command execution due to improperly terminated comment in address list.
View DetailsInformation hiding using a manipulation involving injection of comment code into product. Note: these vulnerabilities are likely vulnerable to more general XSS problems, although a regexp might allow ">!--" while denying most other tags.
View DetailsInformation hiding using a manipulation involving injection of comment code into product. Note: these vulnerabilities are likely vulnerable to more general XSS problems, although a regexp might allow "<!--" while denying most other tags.
View DetailsCWE-151: Improper Neutralization of Comment Delimiters is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as comment delimiters when they are sent to a downstream component.
If exploited, CWE-151 (Improper Neutralization of Comment Delimiters) it can compromise Integrity, leading to outcomes such as Unexpected State.
Recommended mitigations for CWE-151 include: Developers should anticipate that comments will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected and appropriate input is processed by the system.
CWE-151 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-151, including CVE-2002-0001, CVE-2004-0162, CVE-2004-1686, CVE-2005-1909 and CVE-2005-1969. 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-151 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.