Security Digest · Vulnerability record

CVE-2026-35392: goshs: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in goshs PUT Upload

goshs is a SimpleHTTPServer written in Go.

CVSS 9.8 Critical EPSS 0.7% · p52

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

  • Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
  • EPSS 0.7%, percentile 52: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 52% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
  • Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
  • Only applies if your dependency tree includes github.com/patrickhener/goshs (Go) < 1.1.5-0.20260401172448-237f3af891a9, fixed in 1.1.5-0.20260401172448-237f3af891a9. Check your lockfile, including transitive dependencies.

What it is

goshs is a SimpleHTTPServer written in Go. Prior to 2.0.0-beta.3, PUT upload in httpserver/updown.go has no path sanitization. This vulnerability is fixed in 2.0.0-beta.3.

From the GitHub advisory

Summary PUT upload has no path sanitization | httpserver/updown.go:20-69

This finding affects the default configuration, no flags or authentication required.

Details

File: httpserver/updown.go:20-69 Trigger: PUT / (server.go:57-59 routes directly to put())

The handler uses req.URL.Path raw to build the save path. No filepath.Clean, no .. check, no webroot containment.

Weakness type: CWE-22.

Product: github.com/patrickhener/goshs (Go) · Assigned by: GitHub_M · Published: 2026-04-06

Affected and fixed versions

EcosystemPackageVulnerableFirst fixed
Gogithub.com/patrickhener/goshs< 1.1.5-0.20260401172448-237f3af891a91.1.5-0.20260401172448-237f3af891a9
VendorProductAffected versions (per CVE record)
patrickhenergoshs< 2.0.0-beta.3

Severity scores

Scored byCVSSScoreVector
GitHub_M3.09.8 CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
GitHub3.19.8 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • Attack vector: network (remotely reachable)
  • Attack complexity: low
  • Privileges required: none (no login)
  • User interaction: none
  • Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

  • CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
  • CISA SSVC assessment: exploitation poc, automatable yes, technical impact total.
  • FIRST EPSS (model of 2026-10-21): 0.69% probability of exploitation activity in the next 30 days; percentile 52.

Timeline

  • — GitHub-reviewed advisory GHSA-g8mv-vp7j-qp64 published (critical)
  • — CVE record published by GitHub_M
  • — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

  1. GitHub Advisory GHSA-g8mv-vp7j-qp64 github.com
  2. CVE.org record CVE-2026-35392 cve.org
  3. NVD entry CVE-2026-35392 nvd.nist.gov

Other references from the CVE record and advisory

  1. github.com github.com

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