CVE-2018-7159
MediumCVSS 5.3Exploitation Probability (EPSS)
High risk89th percentile - higher than 89% of all known CVEs
Summary
The HTTP parser in all current versions of Node.js ignores spaces in the Content-Length header, allowing input such as 'Content-Length: 1 2' to be interpreted as having a value of '12'. The HTTP specification does not allow for spaces in the Content-Length value and the Node.js HTTP parser has been brought into line on this particular difference. The security risk of this flaw to Node.js users is considered to be VERY LOW as it is difficult, and may be impossible, to craft an attack that makes use of this flaw in a way that could not already be achieved by supplying an incorrect value for Content-Length. Vulnerabilities may exist in user-code that make incorrect assumptions about the potential accuracy of this value compared to the actual length of the data supplied. Node.js users crafting lower-level HTTP utilities are advised to re-check the length of any input supplied after parsing is complete.
Risk Assessment
The vulnerability may lead to incorrect interpretations of content length, which combined with incorrect assumptions in user code could enable request smuggling or other HTTP request manipulations.
Recommendation
Update Node.js to the latest version that includes the fix, and review application code for assumptions about content length.
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Original NVD description (English source)
The HTTP parser in all current versions of Node.js ignores spaces in the `Content-Length` header, allowing input such as `Content-Length: 1 2` to be interpreted as having a value of `12`. The HTTP specification does not allow for spaces in the `Content-Length` value and the Node.js HTTP parser has been brought into line on this particular difference. The security risk of this flaw to Node.js users is considered to be VERY LOW as it is difficult, and may be impossible, to craft an attack that makes use of this flaw in a way that could not already be achieved by supplying an incorrect value for `Content-Length`. Vulnerabilities may exist in user-code that make incorrect assumptions about the potential accuracy of this value compared to the actual length of the data supplied. Node.js users crafting lower-level HTTP utilities are advised to re-check the length of any input supplied after parsing is complete.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS