Run static analysis (SAST) on the codebase looking for the unsafe pattern in the data flow.
CWE-213 Base Draft
Exposure of Sensitive Information Due to Incompatible Policies
This vulnerability occurs when a system's data handling aligns with the developer's security rules but accidentally reveals information that other stakeholders—like users or administrators—consider…
Definition
What is CWE-213?
This vulnerability occurs when a system's data handling aligns with the developer's security rules but accidentally reveals information that other stakeholders—like users or administrators—consider confidential. Essentially, the developer's policy conflicts with the security expectations of the people who use or manage the product.
When building software, developers must recognize that different groups have their own security expectations for the data involved. Users, administrators, and other stakeholders each have an implicit "security contract" they expect the product to honor. A vulnerability arises when the developer's internal policy treats certain information as non-sensitive, while these other parties rely on it being kept private.
To prevent this, you need to proactively identify all data stakeholders and understand what they consider confidential, even if your own design doesn't mark it as such. This means looking beyond your immediate requirements and validating data handling against the real-world privacy and security needs of everyone affected by the system.
Real-world impact
Real-world CVEs caused by CWE-213
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Script calls phpinfo()
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Script calls phpinfo()
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Script calls phpinfo()
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Script calls phpinfo()
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Script calls phpinfo()
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Product lists DLLs and full pathnames.
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Telnet protocol allows servers to obtain sensitive environment information from clients.
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Telnet protocol allows servers to obtain sensitive environment information from clients.
How attackers exploit it
Step-by-step attacker path
- 1
Identify a code path that handles untrusted input without validation.
- 2
Craft a payload that exercises the unsafe behavior — injection, traversal, overflow, or logic abuse.
- 3
Deliver the payload through a normal request and observe the application's reaction.
- 4
Iterate until the response leaks data, executes attacker code, or escalates privileges.
Vulnerable code example
Vulnerable JSP
This code displays some information on a web page.
Social Security Number: <%= ssn %></br>Credit Card Number: <%= ccn %> Secure code example
Secure pseudo
// Validate, sanitize, or use a safe API before reaching the sink.
function handleRequest(input) {
const safe = validateAndEscape(input);
return executeWithGuards(safe);
} What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.
Prevention checklist
How to prevent CWE-213
- Architecture Use safe-by-default frameworks and APIs that prevent the unsafe pattern from being expressible.
- Implementation Validate input at trust boundaries; use allowlists, not denylists.
- Implementation Apply the principle of least privilege to credentials, file paths, and runtime permissions.
- Testing Cover this weakness in CI: SAST rules + targeted unit tests for the data flow.
- Operation Monitor logs for the runtime signals listed in the next section.
Detection signals
How to detect CWE-213
Run dynamic application security testing against the live endpoint.
Watch runtime logs for unusual exception traces, malformed input, or authorization bypass attempts.
Code review: flag any new code that handles input from this surface without using the validated framework helpers.
CWE-213
Don't catalog this weakness. Prove it's reachable.
Plexicus turns CWE catalogs into evidence: every CWE-pattern is matched against your real code graph, reach is proven on a sandbox clone, and verified findings ship as reviewed PRs.
Frequently asked questions What is CWE-213?
How serious is CWE-213?
What languages or platforms are affected by CWE-213?
How can I prevent CWE-213?
How does Plexicus detect and fix CWE-213?
Where can I learn more about CWE-213?
Frequently asked questions
What is CWE-213?
This vulnerability occurs when a system's data handling aligns with the developer's security rules but accidentally reveals information that other stakeholders—like users or administrators—consider confidential. Essentially, the developer's policy conflicts with the security expectations of the people who use or manage the product.
How serious is CWE-213?
MITRE has not published a likelihood-of-exploit rating for this weakness. Treat it as medium-impact until your threat model proves otherwise.
What languages or platforms are affected by CWE-213?
MITRE has not specified affected platforms for this CWE — it can apply across most application stacks.
How can I prevent CWE-213?
Use safe-by-default frameworks, validate untrusted input at trust boundaries, and apply the principle of least privilege. Cover the data-flow signature in CI with SAST.
How does Plexicus detect and fix CWE-213?
Plexicus's SAST engine matches the data-flow signature for CWE-213 on every commit. When a match is found, our Codex Remedium agent opens a fix PR with the corrected code, tests, and a one-line summary for the reviewer.
Where can I learn more about CWE-213?
MITRE publishes the canonical definition at https://cwe.mitre.org/data/definitions/213.html. You can also reference OWASP and NIST documentation for adjacent guidance.
Related weaknesses
Weaknesses related to CWE-213
CWE-200 Parent
Exposure of Sensitive Information to an Unauthorized Actor
This weakness occurs when an application unintentionally reveals sensitive data to someone who shouldn't have access to it.
CWE-1258 Sibling
Exposure of Sensitive System Information Due to Uncleared Debug Information
This vulnerability occurs when hardware fails to erase sensitive data like cryptographic keys and intermediate values before entering…
CWE-1273 Sibling
Device Unlock Credential Sharing
This vulnerability occurs when the secret keys or passwords required to unlock a device's hidden features are shared between multiple…
CWE-1295 Sibling
Debug Messages Revealing Unnecessary Information
The product's debug messages or logs expose excessive internal system details, potentially revealing sensitive information that could aid…
CWE-1431 Sibling
Driving Intermediate Cryptographic State/Results to Hardware Module Outputs
This vulnerability occurs when a hardware cryptographic module leaks sensitive internal data through its output channels. Instead of only…
CWE-201 Sibling
Insertion of Sensitive Information Into Sent Data
This vulnerability occurs when an application sends data to an external party, but accidentally includes sensitive information—like…
CWE-203 Sibling
Observable Discrepancy
This vulnerability occurs when an application responds differently to unauthorized users based on internal conditions. Attackers can…
CWE-209 Sibling
Generation of Error Message Containing Sensitive Information
This vulnerability occurs when an application reveals sensitive details about its internal systems, user data, or environment within error…
CWE-215 Sibling
Insertion of Sensitive Information Into Debugging Code
This vulnerability occurs when developers embed sensitive data, such as passwords or API keys, within debugging statements like logs or…
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