CVE-2026-49143 (GCVE-0-2026-49143)
Vulnerability from cvelistv5 – Published: 2026-06-02 20:31 – Updated: 2026-11-08 14:04 Unsupported When Assigned X_Open Source
VLAI
EPSS
VEX
Title
BrowserStack Runner 0.9.5 Unauthenticated RCE via /_log HTTP Handler
Summary
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 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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-03 14:02 UTC
CWE
- CWE-94 - Improper Control of Generation of Code ('Code Injection')
Assigner
VulnCheck
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/browserstack/browserstack-runn… | vendor-advisory |
| https://www.vulncheck.com/advisories/browserstack… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| browserstack | browserstack-runner |
Affected:
0 , ≤ 0.9.5
(semver)
cpe:2.3:a:browserstack:browserstack-local:*:*:*:*:*:node.js:*:* |
Date Public
2026-05-26 00:00
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Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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