Cyber Resilience

CVE-2026-49402

HighPublic PoCRCE

Published: 23 June 2026

Published
23 June 2026
Modified
26 June 2026
KEV Added
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Patch
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CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0028 20.1th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-49402 is a high-severity OS Command Injection (CWE-78) vulnerability in Deno Deno. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Windows Command Shell (T1059.003); ranked at the 20.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability details

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.10, Deno's node:child_process implementation provided an escapeShellArg() helper used when callers passed shell: true to spawn / spawnSync / exec and friends. On Windows, the helper failed to quote arguments…

more

that contained cmd.exe metacharacters and did not neutralize % (which cmd.exe expands even inside double-quoted strings). An attacker who controlled any portion of an argument passed to such a call could inject arbitrary additional commands into the spawned cmd.exe invocation. This vulnerability is fixed in 2.7.10.

CWE(s)
CWE-78

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Why these techniques?

CWE-78 OS command injection via unsanitized arguments to cmd.exe (shell:true) directly enables arbitrary Windows Command Shell execution (T1059.003); the flaw can be triggered by exploiting a vulnerable application (T1190).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

deno
deno
≤ 2.7.10

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-27 Platform-independent Applications
addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

SI-10 Information Input Validation
addresses: CWE-78

Validates inputs to block special elements that would alter OS command execution.

References