CVE-2018-12121
HighCVSS 7.5Exploitation Probability (EPSS)
Very high risk96th percentile - higher than 96% of all known CVEs
Summary
Node.js versions prior to 6.15.0, 8.14.0, 10.14.0, and 11.3.0 are vulnerable to denial of service with large HTTP headers. By combining many requests with maximum-sized headers (almost 80 KB per connection) and carefully timed completion, the HTTP server can abort due to heap allocation failure. Attack potential is mitigated by a load balancer or proxy layer.
Risk Assessment
An attacker can cause unavailability of the HTTP server, leading to application downtime.
Recommendation
Update Node.js to version 6.15.0, 8.14.0, 10.14.0, 11.3.0 or later.
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Original NVD description (English source)
Node.js: All versions prior to Node.js 6.15.0, 8.14.0, 10.14.0 and 11.3.0: Denial of Service with large HTTP headers: By using a combination of many requests with maximum sized headers (almost 80 KB per connection), and carefully timed completion of the headers, it is possible to cause the HTTP server to abort from heap allocation failure. Attack potential is mitigated by the use of a load balancer or other proxy layer.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

