CVE-2026-50139 patrickhener CVE debrief

Who should care

Defenders responsible for goshs SimpleHTTPServer deployments should assess exposure and verify versions. System administrators and security teams need to ensure that patches are applied to prevent concurrent downloads from exceeding intended limits.

Why it matters

CVE-2026-50139 in goshs SimpleHTTPServer allows concurrent downloads to bypass intended limits, potentially leading to increased resource consumption and server load. Defenders should assess exposure, verify versions, and apply patches to prevent this issue.

• Download limit bypass allows unintended resource consumption.
• Concurrent requests can lead to increased server load.
• Verification of version and patch application is necessary.
• Exposure assessment is required for goshs SimpleHTTPServer deployments.

Technical summary

CVE-2026-50139 is a vulnerability in goshs SimpleHTTPServer where the ShareHandler allows concurrent requests to bypass the intended download limit. This occurs because the server reads the share token's DownloadLimit under RLock, releases the lock, serves the file, then re-acquires the lock to increment the counter. As a result, multiple requests can pass the check and be served simultaneously, exceeding the operator's intended cap. The issue is patched in version 2.1.0.

Defensive priority

Assess exposure, verify version, and apply patches for goshs SimpleHTTPServer.

Recommended defensive actions

• Assess exposure to CVE-2026-50139 in goshs SimpleHTTPServer deployments.
• Verify if versions prior to 2.1.0 are in use and apply patches if necessary.
• Monitor for concurrent download requests that could exceed intended limits.
• Review server logs for unusual download patterns.
• Implement compensating controls for exposed systems.
• Track exceptions and retest remediated assets.
• Close the item only after evidence is documented.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability in goshs SimpleHTTPServer. The issue allows concurrent requests to exceed the intended download limit due to a race condition in the ShareHandler. Evidence is based on CVE Program and NVD sources, with limitations on affected scope and vendor guidance. Defenders should verify versions, assess exposure, and apply patches. Additional review of server logs and monitoring for concurrent download requests is recommended.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.