Review reviewHigh

CVE-2026-49144

browserstack browserstack-runner

BrowserStack Runner through 0.9.5 contains a path traversal vulnerability in the _default HTTP handler in lib/server.js that allows unauthenticated network-adjacent attackers to read arbitrary files. Attackers can exploit the unauthenticated HTTP server bound on all interfaces to traverse outside the project root and access sensitive files.

CVSS
7.1
EPSS
0.21%
11.1% percentile
CISA KEV
Not listed
Published
2026.06.03
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.21%
Technical severityCVSS 7.1

Vulnerability overview

BrowserStack Runner through 0.9.5 contains a path traversal vulnerability in the _default HTTP handler in lib/server.js that allows unauthenticated network-adjacent attackers to read arbitrary files. Attackers can exploit the unauthenticated HTTP server bound on all interfaces to traverse outside the project root and access sensitive files.

Affected product and versions

Product
browserstack browserstack-runner
Affected versions
<= 0.9.5
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that browserstack browserstack-runner and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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
CWE
CWE-22
CVE-2026-49144 — browserstack browserstack-runner | SECUFOCUS NOW