CVE-2025-59464
Published: 20 January 2026
Summary
CVE-2025-59464 is a high-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Nodejs Node.Js. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 19.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SC-5 (Denial-of-service Protection) and SC-6 (Resource Availability).
Deeper analysis
CVE-2025-59464 is a memory leak vulnerability in Node.js's OpenSSL integration. The issue arises when X.509 certificate fields are converted to UTF-8 without freeing the allocated buffer. This leak occurs each time an application calls socket.getPeerCertificate(true), affecting Node.js applications that process TLS peer certificates.
Remote unauthenticated attackers can exploit this vulnerability by initiating repeated TLS connections to vulnerable Node.js servers. Each connection triggers memory leakage proportional to the certificate fields processed, causing gradual memory growth. Over time, this leads to resource exhaustion and denial-of-service. The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) and maps to CWE-400 (Uncontrolled Resource Consumption).
The Node.js security advisory at https://nodejs.org/en/blog/vulnerability/december-2025-security-releases provides details on patches addressing this issue, published on 2026-01-20.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-3340
Vulnerability details
A memory leak in Node.js’s OpenSSL integration occurs when converting `X.509` certificate fields to UTF-8 without freeing the allocated buffer. When applications call `socket.getPeerCertificate(true)`, each certificate field leaks memory, allowing remote clients to trigger steady memory growth through repeated TLS…
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connections. Over time this can lead to resource exhaustion and denial of service.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Direct remote exploitation of public-facing Node.js TLS endpoint for memory exhaustion DoS via repeated connections.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Flaw remediation requires timely patching of the Node.js OpenSSL memory leak vulnerability to eliminate the root cause of resource exhaustion.
Denial-of-service protection limits repeated TLS connections from remote attackers, preventing steady memory growth via certificate field processing.
Resource availability protections enforce memory limits on Node.js processes to block exhaustion from unfreed buffers during X.509 to UTF-8 conversions.