Deno: Miller-Rabin Primality Test Allows Zero Rounds_CVE-2026-49440

7.4 / 10

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, node:crypto.checkPrime(candidate[, options][, callback]) and crypto.checkPrimeSync(candidate[, options]) ran no Miller-Rabin rounds at all when the caller left options.checks at its default of 0. In that mode, the only test applied to the candidate was trial division by the primes up to 17,863. Any composite whose smallest prime factor exceeds that bound — for example the product of two primes just above it, such as 17,881 × 17,891 — was reported as true ("probably prime"). The same divergence affected the lower-level op_node_check_prime / op_node_check_prime_bytes paths that the polyfill calls into. This vulnerability is fixed in 2.8.1.

Basic Information

ID CVE-2026-49440

Source GitHub_M

Published Jun 23, 2026 at 17:13

Affected Product

Vendor denoland

Product deno

Version < 2.8.1

Affected Versions denoland deno < 2.8.1

CWE Classification

CWE-325

References

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    "published": "2026-06-23T17:13:25.052Z",
    "modified": "2026-06-23T17:13:25.052Z",
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