Answer in brief
CVE-2026-49143 records a Unknown severity vulnerability in BrowserStack Runner 0.9.5 Unauthenticated RCE via /_log HTTP Handler. The current sources do not mark it as known exploited. The current feed maps browserstack/browserstack-runner (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps browserstack/browserstack-runner (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| browserstack/browserstack-runnergeneric | 0 | Not reported |
Published upstream
Jun 2, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 14, 2026
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.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-49143 records a Unknown severity vulnerability in BrowserStack Runner 0.9.5 Unauthenticated RCE via /_log HTTP Handler. The current sources do not mark it as known exploited. The current feed maps browserstack/browserstack-runner (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps browserstack/browserstack-runner (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| browserstack/browserstack-runnergeneric | 0 | Not reported |
Published upstream
Jun 2, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 14, 2026
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.
Quoted source text, attributed separately from HOL analysis.