CWE-565: Reliance on Cookies without Validation and Integrity Checking
Official CWE-565 CWE context with Glexia analysis, remediation guidance, related CVEs, and ATT&CK context.
Glexia's Take
CWE-565: Reliance on Cookies without Validation and Integrity Checking
Reliance on Cookies without Validation and Integrity Checking represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Confidentiality,Integrity,Availability: Modify Application Data,Execute Unauthorized Code or Commands: Attackers can easily modify cookies, within the browser or by implementing the client-side code outside of the browser. Reliance on cookies without detailed validation and integrity checking can allow attackers to bypass authentication, conduct injection attacks such as SQL injection and cross-site scripting, or otherwise modify inputs in unexpected ways.
- Access Control: Gain Privileges or Assume Identity: It is dangerous to use cookies to set a user's privileges. The cookie can be manipulated to escalate an attacker's privileges to an administrative level.
Developer Pattern
CWE-565 is the kind of defect developers can usually prevent with explicit validation, safer framework defaults, and tests that exercise hostile input or unsafe state transitions.
Confidence
high confidence from CWE-565, 4.20.
Official CWE Definition
CWE-565: Reliance on Cookies without Validation and Integrity Checking
The product relies on the existence or values of cookies when performing security-critical operations, but it does not properly ensure that the setting is valid for the associated user.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- The following code excerpt reads a value from a browser cookie to determine the role of the user. It is easy for an attacker to modify the "role" value found in the locally stored cookie, allowing privilege escalation.
Remediation
- Architecture and Design: Avoid using cookie data for a security-related decision.
- Implementation: Perform thorough input validation (i.e.: server side validation) on the cookie data if you're going to use it for a security related decision.
- Architecture and Design: Add integrity checks to detect tampering.
- Architecture and Design: Protect critical cookies from replay attacks, since cross-site scripting or other attacks may allow attackers to steal a strongly-encrypted cookie that also passes integrity checks. This mitigation applies to cookies that should only be valid during a single transaction or session. By enforcing timeouts, you may limit the scope of an attack. As part of your integrity check, use an unpredictable, server-side value that is not exposed to the client.
Detection
- Automated Static Analysis: 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.)
Mappings
Related CVEs, CWEs, and ATT&CK context
Related CWEs
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.