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CVE-2026-49406

Status: AnalyzedMedium (5.5)—

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.12, when Deno was run in BYONM mode (nodeModulesDir: "manual"), the module resolver did not validate that a package's resolved entrypoint stayed within its node_modules/<pkg>/ directory. A malicious package.json whose main field contained .. segments was able to resolve to an arbitrary path on disk, and the resolver then read that file without consulting the --allow-read allowlist. This let a require("evil-pkg") call return the contents of a file that a direct Deno.readTextFileSync(...) call would have been blocked from reading. This vulnerability is fixed in 2.7.12.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Deno — Deno

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2026-49406",
  "cveTags": [],
  "metrics": {
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          "options": [
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          "version": "2.0.3",
          "timestamp": "2026-06-23T17:49:51.311695Z"
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
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  "published": "2026-06-23T18:18:03.310",
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    }
  ],
  "lastModified": "2026-06-26T17:29:09.427",
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