CVE-2018-25077 in mel-spintax
Summary
by MITRE • 01/18/2023
A vulnerability was found in melnaron mel-spintax. It has been rated as problematic. Affected by this issue is some unknown functionality of the file lib/spintax.js. The manipulation of the argument text leads to inefficient regular expression complexity. The name of the patch is 37767617846e27b87b63004e30216e8f919637d3. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-218456.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 02/09/2023
The vulnerability identified as CVE-2018-25077 resides within the melnaron mel-spintax library, specifically affecting the lib/spintax.js file through a problematic implementation of regular expression processing. This issue represents a classic example of a regular expression denial of service vulnerability where malicious input can cause exponential execution time, making the system unresponsive or vulnerable to resource exhaustion attacks. The flaw manifests when the argument text parameter is manipulated, triggering inefficient regular expression complexity that can be exploited by attackers to consume excessive computational resources.
This vulnerability falls under the CWE-400 category of Uncontrolled Resource Consumption, specifically related to regular expression complexity issues. The attack vector involves crafting input text that, when processed through the spintax.js library, causes the regular expressions to enter catastrophic backtracking states. The patch identifier 37767617846e27b87b63004e30216e8f919637d3 suggests a specific fix that likely involves optimizing the regular expressions or implementing input validation to prevent overly complex pattern matching operations. The vulnerability's designation as VDB-218456 indicates it was catalogued in the Vulnerability Database, highlighting its recognition within the security community.
The operational impact of this vulnerability extends beyond simple performance degradation, as it can be leveraged to create denial of service conditions that affect the availability of services relying on the mel-spintax library. Systems processing user input through this library become susceptible to attacks where malicious actors can craft text patterns that cause the application to hang or consume excessive CPU resources. This makes the vulnerability particularly dangerous in web applications or services where input validation is not properly implemented, potentially allowing attackers to disrupt service availability or consume server resources for extended periods.
Mitigation strategies should focus on implementing proper input validation and sanitization before processing text through the spintax.js library. The recommended approach involves applying the specific patch referenced in the vulnerability report, which likely modifies the regular expression patterns to prevent catastrophic backtracking scenarios. Additionally, implementing timeouts for regular expression operations and establishing maximum input length limits can provide defense-in-depth measures. Organizations should also consider adopting the ATT&CK framework's T1499.004 technique of resource exhaustion prevention, ensuring that applications are hardened against such computational complexity attacks. Regular security assessments and code reviews should be conducted to identify similar patterns in other regular expression implementations within the codebase, preventing similar vulnerabilities from emerging in other components.