Cyber Resilience

CVE-2026-49143

HighPublic PoCUpdated

Published: 02 June 2026

Published
02 June 2026
Modified
17 June 2026
KEV Added
Patch
CVSS Score v4 8.7 CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0039 31.1th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-49143 is a high-severity Code Injection (CWE-94) vulnerability. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 31.1th 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)

EU & UK References

Vulnerability details

BrowserStack Runner through 0.9.5 contains a remote code execution vulnerability in the /_log HTTP handler that allows unauthenticated network-adjacent attackers to execute arbitrary code by submitting crafted JSON request bodies to the handler, which passes user-supplied data to vm.runInNewContext() combined…

more

with eval(). Attackers can escape the Node.js vm sandbox by leveraging a host-context Function reference through util.format to access the host process via this.constructor.constructor, achieving full remote code execution on the underlying system without any authentication.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

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.
Why these techniques?

Direct RCE via unauthenticated crafted requests to exposed HTTP handler in public-facing application (CWE-94 code injection).

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

CVEs Like This One

CVE-2021-47939Shared CWE-94
CVE-2026-41229Shared CWE-94
CVE-2026-44262Shared CWE-94
CVE-2026-26045Shared CWE-94
CVE-2025-33239Shared CWE-94
CVE-2024-11600Shared CWE-94
CVE-2025-41717Shared CWE-94
CVE-2025-67979Shared CWE-94
CVE-2026-28425Shared CWE-94
CVE-2025-21187Shared CWE-94

Affected Assets

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.

addresses: CWE-94

Makes persistent code injection into loaded programs impossible when the executable image itself resides on hardware-protected read-only media.

addresses: CWE-94

Dynamically generated code can be produced and executed inside the isolated chamber, preventing host compromise from code-injection payloads.

addresses: CWE-94

Validates inputs used in dynamic code generation to block injected directives.

addresses: CWE-94

Directly prevents execution of attacker-supplied code written into data memory regions.

References