high8.8
CVE-2026-49143
BrowserStack Runner through 0.9.5 contains a remote code execution vulnerability in the /_log HTTP handler that allows unauthenticated network-adjacent attacke…
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | browserstack-runner | <= 0.9.5 | none recorded |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-6vr3-7wcx-v5g5
- https://github.com/browserstack/browserstack-runner/security/advisories/GHSA-6vr3-7wcx-v5g5
- https://nvd.nist.gov/vuln/detail/CVE-2026-49143
- https://www.vulncheck.com/advisories/browserstack-runner-unauthenticated-rce-via-log-http-handler