结构: Simple
Abstraction: Base
状态: Draft
被利用可能性: unkown
The software filters data in a way that causes it to be reduced or "collapsed" into an unsafe value that violates an expected security property.
cwe_Nature: ChildOf cwe_CWE_ID: 693 cwe_View_ID: 1000 cwe_Ordinal: Primary
cwe_Nature: CanPrecede cwe_CWE_ID: 33 cwe_View_ID: 1000
cwe_Nature: CanPrecede cwe_CWE_ID: 34 cwe_View_ID: 1000
cwe_Nature: CanPrecede cwe_CWE_ID: 35 cwe_View_ID: 1000
Language: {'cwe_Class': 'Language-Independent', 'cwe_Prevalence': 'Undetermined'}
范围 | 影响 | 注释 |
---|---|---|
Access Control | Bypass Protection Mechanism |
策略: Input Validation
Avoid making decisions based on names of resources (e.g. files) if those resources can have alternate names.
策略: Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a whitelist of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs (i.e., do not rely on a blacklist). A blacklist is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, blacklists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
策略: Input Validation
Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass whitelist validation schemes by introducing dangerous inputs after they have been checked.
策略:
Canonicalize the name to match that of the file system's representation of the name. This can sometimes be achieved with an available API (e.g. in Win32 the GetFullPathName function).
标识 | 说明 | 链接 |
---|---|---|
CVE-2004-0815 | "/.////" in pathname collapses to absolute path. | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2004-0815 |
CVE-2005-3123 | "/.//..//////././" is collapsed into "/.././" after ".." and "//" sequences are removed. | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-3123 |
CVE-2002-0325 | ".../...//" collapsed to "..." due to removal of "./" in web server. | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-0325 |
CVE-2002-0784 | chain: HTTP server protects against ".." but allows "." variants such as "////./../.../". If the server removes "/.." sequences, the result would collapse into an unsafe value "////../" (CWE-182). | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-0784 |
CVE-2005-2169 | MFV. Regular expression intended to protect against directory traversal reduces ".../...//" to "../". | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-2169 |
CVE-2001-1157 | XSS protection mechanism strips a |