Use monitoring tools that examine the software's process as it interacts with the operating system and the network. This technique is useful in cases when source code is unavailable, if the software was not developed by you, or if you want to verify that the build phase did not introduce any new weaknesses. Examples include debuggers that directly attach to the running process; system-call tracing utilities such as truss (Solaris) and strace (Linux); system activity monitors such as FileMon, RegMon, Process Monitor, and other Sysinternals utilities (Windows); and sniffers and protocol analyzers that monitor network traffic. Attach the monitor to the process, trigger the feature that sends the data, and look for the presence or absence of common cryptographic functions in the call tree. Monitor the network and determine if the data packets contain readable commands. Tools exist for detecting if certain encodings are in use. If the traffic contains high entropy, this might indicate the usage of encryption.
Cleartext Transmission of Sensitive Information
This vulnerability occurs when an application sends sensitive data, such as passwords or personal information, over a network connection without using encryption. Attackers can easily intercept and…
What is CWE-319?
Real-world CVEs caused by CWE-319
-
Programmable Logic Controller (PLC) sends sensitive information in plaintext, including passwords and session tokens.
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Building Controller uses a protocol that transmits authentication credentials in plaintext.
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Programmable Logic Controller (PLC) sends password in plaintext.
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Passwords transmitted in cleartext.
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Chain: Use of HTTPS cookie without "secure" flag causes it to be transmitted across unencrypted HTTP.
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Product sends password hash in cleartext in violation of intended policy.
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Remote management feature sends sensitive information including passwords in cleartext.
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Backup routine sends password in cleartext in email.
Step-by-step attacker path
- 1
The following code attempts to establish a connection to a site to communicate sensitive information.
- 2
Though a connection is successfully made, the connection is unencrypted and it is possible that all sensitive data sent to or received from the server will be read by unintended actors.
- 3
In 2022, the OT:ICEFALL study examined products by 10 different Operational Technology (OT) vendors. The researchers reported 56 vulnerabilities and said that the products were "insecure by design" [REF-1283]. If exploited, these vulnerabilities often allowed adversaries to change how the products operated, ranging from denial of service to changing the code that the products executed. Since these products were often used in industries such as power, electrical, water, and others, there could even be safety implications.
- 4
Multiple vendors used cleartext transmission of sensitive information in their OT products.
- 5
A TAP accessible register is read/written by a JTAG based tool, for internal use by authorized users. However, an adversary can connect a probing device and collect the values from the unencrypted channel connecting the JTAG interface to the authorized user, if no additional protections are employed.
Vulnerable Java
The following code attempts to establish a connection to a site to communicate sensitive information.
try {
URL u = new URL("http://www.secret.example.org/");
HttpURLConnection hu = (HttpURLConnection) u.openConnection();
hu.setRequestMethod("PUT");
hu.connect();
OutputStream os = hu.getOutputStream();
hu.disconnect();
}
catch (IOException e) {
```
//...*
}Secure Shell
Azure's storage accounts can be configured to only accept requests from secure connections made over HTTPS. The secure transfer setting can be enabled using Azure's Portal (GUI) or programmatically by setting the enableHttpsTrafficOnly property to True on the storage account, such as:
az storage account update -g {ResourceGroupName} -n {StorageAccountName} --https-only trueHow to prevent CWE-319
- Architecture and Design Before transmitting, encrypt the data using reliable, confidentiality-protecting cryptographic protocols.
- Implementation When using web applications with SSL, use SSL for the entire session from login to logout, not just for the initial login page.
- Implementation When designing hardware platforms, ensure that approved encryption algorithms (such as those recommended by NIST) protect paths from security critical data to trusted user applications.
- Testing Use tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session. These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.
- Operation Configure servers to use encrypted channels for communication, which may include SSL or other secure protocols.
How to detect CWE-319
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
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Frequently asked questions
What is CWE-319?
This vulnerability occurs when an application sends sensitive data, such as passwords or personal information, over a network connection without using encryption. Attackers can easily intercept and read this unprotected data as it travels.
How serious is CWE-319?
MITRE rates the likelihood of exploit as High — this weakness is actively exploited in the wild and should be prioritized for remediation.
What languages or platforms are affected by CWE-319?
MITRE lists the following affected platforms: Cloud Computing, Mobile, ICS/OT, System on Chip, Test/Debug Hardware.
How can I prevent CWE-319?
Before transmitting, encrypt the data using reliable, confidentiality-protecting cryptographic protocols. When using web applications with SSL, use SSL for the entire session from login to logout, not just for the initial login page.
How does Plexicus detect and fix CWE-319?
Plexicus's SAST engine matches the data-flow signature for CWE-319 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-319?
MITRE publishes the canonical definition at https://cwe.mitre.org/data/definitions/319.html. You can also reference OWASP and NIST documentation for adjacent guidance.
Weaknesses related to CWE-319
Missing Encryption of Sensitive Data
This vulnerability occurs when an application stores or sends sensitive information without first encrypting it, leaving the data exposed.
Cleartext Storage of Sensitive Information
This vulnerability occurs when an application stores sensitive data like passwords, credit card numbers, or personal information in plain…
Reliance on HTTP instead of HTTPS
This vulnerability occurs when an application uses unencrypted HTTP connections instead of the secure HTTPS alternative, even when HTTPS…
J2EE Misconfiguration: Data Transmission Without Encryption
This vulnerability occurs when a J2EE application transmits sensitive data, like login credentials or session tokens, across a network…
Sensitive Cookie in HTTPS Session Without 'Secure' Attribute
This vulnerability occurs when a web application transmits sensitive cookies over an HTTPS connection but fails to set the 'Secure'…
Further reading
- MITRE — official CWE-319 https://cwe.mitre.org/data/definitions/319.html
- Top 10 2007-Insecure Communications https://web.archive.org/web/20160319230109/http://www.owasp.org/index.php/Top_10_2007-A9
- Writing Secure Code https://www.microsoftpressstore.com/store/writing-secure-code-9780735617223
- Mobile App Top 10 List https://www.veracode.com/blog/2010/12/mobile-app-top-10-list
- OT:ICEFALL: The legacy of "insecure by design" and its implications for certifications and risk management https://www.forescout.com/resources/ot-icefall-report/
- CIS Microsoft Azure Foundations Benchmark version 1.5.0 https://www.cisecurity.org/benchmark/azure
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