Cyber Resilience

CVE-2026-49401

Deno ≤ 2.7.14

Public PoC
Published
23 June 2026
Modified
26 June 2026
Patch / advisory
View advisory
CVSS Score v3.1 7.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N
EPSS Score 0.0019 9th percentile
Risk Priority 50 floored blend · peak EPSS

Summary

CVE-2026-49401 is a high-severity Improper Resolution of Path Equivalence (CWE-41) vulnerability in Deno Deno. Its CVSS base score is 7.3 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Invisible Unicode (T1027.018); ranked at the 9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and AC-3 (Access Enforcement) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.14, Deno's permission system enforces filesystem and execution restrictions by comparing the requested path against the path supplied to --deny-read, --deny-write, --deny-run, or --deny-ffi. On macOS, that comparison was done…

more

at the raw-byte level while the APFS filesystem treats different Unicode spellings of the same name as the same file. That means a program could reach a denied path by spelling it differently than the deny rule. This vulnerability is fixed in 2.7.14.

CWE(s)
CWE-41CWE-176

Related Threats

MITRE ATT&CK Enterprise Techniques

T1027.018 Invisible Unicode Stealth
Adversaries may abuse invisible or non-printing Unicode characters to conceal malicious content within files, scripts, or text.
attack.mitre.org →
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
attack.mitre.org →
T1027 Obfuscated Files or Information Stealth
Adversaries may attempt to make an executable or file difficult to discover or analyze by encrypting, encoding, or otherwise obfuscating its contents on the system or in transit.
attack.mitre.org →
T1083 File and Directory Discovery Discovery
Adversaries may enumerate files and directories or may search in specific locations of a host or network share for certain information within a file system.
attack.mitre.org →
T1132 Data Encoding Command And Control
Adversaries may encode data to make the content of command and control traffic more difficult to detect.
attack.mitre.org →
T1132.002 Non-Standard Encoding Command And Control
Adversaries may encode data with a non-standard data encoding system to make the content of command and control traffic more difficult to detect.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

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CVE-2024-40807Same product: Apple Macos
CVE-2025-43231Same product: Apple Macos
CVE-2025-43289Same product: Apple Macos
CVE-2026-28839Same product: Apple Macos
CVE-2025-43403Same product: Apple Macos
CVE-2026-28845Same product: Apple Macos
CVE-2023-40430Same product: Apple Macos
CVE-2026-28881Same product: Apple Macos
CVE-2025-46289Same product: Apple Macos

Affected Assets

deno
deno
≤ 2.7.14

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SI-10 Information Input Validation good match

Input validation of file paths directly rejects or normalizes the special-character manipulations that create equivalent names.

AC-3 Access Enforcement partial match

Proper enforcement of file access authorizations structurally blocks disclosure when equivalent paths are presented.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent introduction of improper path-resolution logic in software.

PR.IR-01 partial match
prevents

Path-equivalence flaws enable unauthorized file access that network segmentation and logical access controls can partially block.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.28 Secure coding mostly match
prevents

Secure coding standards directly require canonical path resolution and input sanitization to prevent equivalence attacks.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect path-equivalence flaws before release, partially fulfilling the control.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle includes path-handling requirements that reduce equivalence-based disclosure.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate canonicalization and input validation to block path equivalence.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles call for safe file-system abstractions that mitigate path traversal risks.

A.8.3 Information access restriction none match
none

Information access restriction limits what files can be reached, indirectly reducing impact of path-equivalence exploits.

References