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{}

{"analysis": {"en": {"generated_at": "2026-03-30T20:23:08.104665+00:00", "value": {"mitigation_remediation": ["Upgrade Node.js to the latest patch release for the affected series, which replaces the insecure comparison with a constant\u2011time primitive.", "If an immediate upgrade is not possible, modify the verification code to use Node.js\u2019s `crypto.timingSafeEqual` function for HMAC comparison.", "Validate that the updated Node.js rebuilds the affected modules and passes security tests or scans.", "Keep monitoring Node.js security advisories for further updates or guidance."], "summary": {"action": "Apply Patch", "impact": "Timing oracle leading to possible HMAC exposure"}, "threat_synthesis": {"affected_systems": "Node.js releases 20.x, 22.x, 24.x, and 25.x contain the vulnerable comparison logic and are impacted by this flaw.", "description_and_impact": "A flaw in Node.js validates user\u2011provided HMAC signatures with a non\u2011constant\u2011time comparison, leaking timing information proportional to matching bytes. This side\u2011channel can be exploited by an attacker with high\u2011resolution timing measurements to infer the correct HMAC value, potentially compromising authentication or message integrity. The weakness aligns with a timing side\u2011channel definition.", "risk_and_exploitability": "The CVSS score of 5.9 indicates moderate severity. Because no EPSS score or KEV listing is present, the probability of real\u2011world exploitation remains uncertain, though timing attacks are feasible when an attacker can observe repeated verification requests. The vulnerability does not directly expose secrets, but it can be a stepping\u2011stone for more destructive attacks if combined with other weaknesses."}}}}, "created": "2026-03-30T20:55:13.070614+00:00", "title": "Timing Side\u2011Channel in Node.js HMAC Verification", "updated": "2026-03-30T20:55:13.070753+00:00", "vendors": [], "weaknesses": ["CWE-203"]}