CVE-2018-12121

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 10.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-11-28 · updated 2026-10-08
Weakness: CWE-400

Description

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.

Affected products

Node.js: from 6.0.0 before 6.15.0; from 8.0.0 before 8.14.0; from 10.0.0 before 10.14.0; from 11.0.0 before 11.3.0 — fixed in 10.14.0, 11.3.0, 6.15.0, 8.14.0
Red Hat Enterprise Linux: 8.0
RedHat Enterprise Linux Desktop: 7.0
RedHat Enterprise Linux Eus: 8.1, 8.2, 8.4, 8.6
RedHat Enterprise Linux Server: 7.0
RedHat Enterprise Linux Server Aus: 8.2, 8.4, 8.6
RedHat Enterprise Linux Server Tus: 8.2, 8.4, 8.6
RedHat Enterprise Linux Workstation: 7.0

How to fix

Upgrade to a fixed version: Node.js 10.14.0, 11.3.0, 6.15.0, 8.14.0. Check the vendor advisory for mitigations.

References

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