CWE-200 is Exposure of Sensitive Information to an Unauthorized Actor. The flaw arises when the product exposes sensitive information to an actor that is not explicitly authorized to access it. The database currently holds 1,421 vulnerabilities mapped to CWE-200 and 2 of them are in the CISA Known Exploited Vulnerabilities catalog.
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. (Roles: Impact-Oriented, Discouraged, Impact-Oriented, Discouraged)
There are many different kinds of mistakes that introduce information exposures. The severity of the error can range widely, depending on the context in which the product operates, the type of sensitive information that is revealed, and the benefits it may provide to an attacker. Some kinds of sensitive information include:
private, personal information, such as personal messages, financial data, health records, geographic location, or contact details
system status and environment, such as the operating system and installed packages
business secrets and intellectual property
network status and configuration
the product's own code or internal state
metadata, e.g. logging of connections or message headers
indirect information, such as a discrepancy between two internal operations that can be observed by an outsider
Information might be sensitive to different parties, each of which may have their own expectations for whether the information should be protected. These parties include:
the product's own users
people or organizations whose information is created or used by the product, even if they are not direct product users
the product's administrators, including the admins of the system(s) and/or networks on which the product operates
the developer
Information exposures can occur in different ways:
the code explicitly inserts sensitive information into resources or messages that are intentionally made accessible to unauthorized actors, but should not contain the information - i.e., the information should have been "scrubbed" or "sanitized"
a different weakness or mistake indirectly inserts the sensitive information into resources, such as a web script error revealing the full system path of the program.
the code manages resources that intentionally contain sensitive information, but the resources are unintentionally made accessible to unauthorized actors. In this case, the information exposure is resultant - i.e., a different weakness enabled the access to the information in the first place.
This is a broad weakness involving disclosure beyond an actor's authorization boundary. Severity depends on the type of information, the operating context, and the value the information provides to an attacker. The protected information may belong to users, individuals or organizations whose data is processed by the product, system or network administrators, or developers.
Exposure can occur in intentionally generated content, such as error messages, debug logs, protocol responses, query results, or other accessible resources. It can also be indirect, through observable timing, error codes, version details, paths, configuration, or discrepancies between internal operations. When another weakness first enables access to a resource containing sensitive information, CWE-200 describes the resulting exposure, while the enabling weakness should be identified separately.
The weakness can be introduced during both architecture and design and implementation, and is not specific to a programming language or technology. Exposed information may include personal, financial, health, location, business, source-code, internal-state, network-configuration, or metadata information, as well as indirect information inferred from behavioral differences.
The main mechanisms are: code explicitly places sensitive data in an accessible resource or message; another weakness indirectly places it there, such as an error revealing a system path; or a resource that legitimately contains sensitive data is unintentionally made accessible. The third mechanism is resultant exposure, where another weakness enables the access.
The recorded consequence is a confidentiality impact: an unauthorized actor can read application data. Depending on the information exposed, this can include personal data, credentials, system or network details, business secrets, source code, internal state, metadata, or information inferred from observable behavior.
| Impact | Scope | Explanation |
|---|---|---|
| Read Application Data | Confidentiality | - |
Architecture and design: compartmentalize the system so that trust boundaries are explicit and sensitive data cannot leave a safe area without appropriate control. Build privilege separation into the design, apply least privilege when deciding when privileges are needed, and drop privileges when they are no longer required. This guidance is primarily preventive at the architecture and design phase.
Multiple methods can be combined, but each has limited coverage in some contexts:
These techniques may miss data flows, error states, or behavioral differences that occur only under particular deployment conditions.
| Method | Approach | Effectiveness |
|---|---|---|
| Automated Static Analysis - Binary or Bytecode | According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Bytecode Weakness Analysis - including disassembler + source code weakness analysis Inter-application Flow Analysis | SOAR Partial |
| Dynamic Analysis with Automated Results Interpretation | According to SOAR [REF-1479], the following detection techniques may be useful: ``` Highly cost effective: ``` Web Application Scanner Web Services Scanner Database Scanners | High |
| Dynamic Analysis with Manual Results Interpretation | According to SOAR [REF-1479], the following detection techniques may be useful: ``` Cost effective for partial coverage: ``` Fuzz Tester Framework-based Fuzzer Automated Monitored Execution Monitored Virtual Environment - run potentially malicious code in sandbox / wrapper / virtual machine, see if it does anything suspicious | SOAR Partial |
| Manual Static Analysis - Source Code | According to SOAR [REF-1479], the following detection techniques may be useful: ``` Highly cost effective: ``` Manual Source Code Review (not inspections) | High |
| Automated Static Analysis - Source Code | According to SOAR [REF-1479], the following detection techniques may be useful: ``` Highly cost effective: ``` Context-configured Source Code Weakness Analyzer ``` Cost effective for partial coverage: ``` Source code Weakness Analyzer | High |
| Architecture or Design Review | According to SOAR [REF-1479], the following detection techniques may be useful: ``` Highly cost effective: ``` Formal Methods / Correct-By-Construction ``` Cost effective for partial coverage: ``` Attack Modeling Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.) | High |
The following are representative examples, not an exhaustive list:
CVE-2022-31162: a Rust library exposes OAuth client details in application debug logs.CVE-2021-25476: a mobile platform DRM capability exposes pointer information, simplifying an ASLR bypass.CVE-2001-1483, CVE-2001-1528, CVE-2004-2150, and CVE-2003-0190: enable enumeration of valid usernames or account numbers through inconsistent responses, error messages, or timing differences.CVE-2005-1205: a Telnet server can obtain sensitive environment information from clients.CVE-2002-1725, CVE-2007-1409, CVE-2005-0603, and CVE-2007-5172: expose system configuration, pathnames, or information from regular-expression and database errors.CVE-2004-2268 and CVE-2003-1078: expose passwords in debug information or when an FTP client's debug option is enabled.CVE-2002-0515, CVE-2004-0778, and CVE-2000-1117: allow attackers to infer port status or file and directory existence through TTL differences, error messages, or execution timing.CVE-2008-2049 and CVE-2008-4638: expose a password or file contents through errors, with the exposure potentially resulting from another weakness.CVE-2022-0708: a collaboration platform fails to clear team email addresses from a response, exposing those addresses.Below are representative vulnerabilities related to this CWE, prioritized by severity.
CWE™ Program, operated by The MITRE Corporation. Copyright © 2006–2026, The MITRE Corporation. The MITRE Corporation hereby grants you a non-exclusive, royalty-free license to use CWE for research, development, and commercial purposes. CWE Terms of Use.
CyStack VulnScan continuously discovers assets, validates vulnerabilities, and helps security teams prioritize remediation across the organization.
Review CyStack's security rating and practical recommendations for websites and edge assets.
Explore cybersecurity research from our team of security specialists.
Browse practical cybersecurity knowledge across CyStack's articles and guides.
en
