Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2017-20284

Caucho Resin doc Unauthenticated Path Traversal

Caucho Technology / Resin · *

View live feed Monitor via API Watch CVE-2017-20284
Severity
CVSS 8.7 · High
Confidence
High
Exploit status
Exploited in the wild
EPSS
1.0%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2017-20284 is an unauthenticated vulnerability affecting Caucho Technology Resin. Caucho Resin contains a path traversal vulnerability in the documentation webapp (resin-doc) that allows remote unauthenticated...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is high. Also confirmed by third-party sources.

Who is affected?

Caucho Technology / Resin *.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Caucho Resin doc Unauthenticated Path Traversal

Caucho Resin contains a path traversal vulnerability in the documentation webapp (resin-doc) that allows remote unauthenticated attackers to read arbitrary files by supplying a relative path through the inputFile request parameter of the jndi-appconfig tutorial servlet. Attackers can craft requests with directory traversal sequences to the servlet endpoint to read files outside the intended tutorial directory on the underlying system.

Exploitation evidence was first observed by the Shadowserver Foundation on 2021-12-10.

Caucho Technology, Inc. Affected
Resin
*
View vendor advisory (opens in new tab)
Published
18 Sep 2026
Exploitation Reported
18 Sep 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2017-20284
  • Third-Party Advisory — vulncheck.com vulncheck.com · Third-Party Advisory https://www.vulncheck.com/advisories/caucho-resin-resin-doc-unauthent...
  • Researcher Blog blkstone.github.io · Exploit https://blkstone.github.io/2017/10/30/resin-attack-vectors/
  • Nuclei Template raw.githubusercontent.com · Technical Description https://raw.githubusercontent.com/projectdiscovery/nuclei-templates/m...
  • Product Webpage caucho.com · Product https://caucho.com/products/resin

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CVE

Recorded 18 Sep 2026

A trusted third party reported exploitation.

Proof of concept available

CVE

Recorded 18 Sep 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

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Source Added
CVE First 2026-09-18 19:20 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v4.0

8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS

1.0%

Weaknesses

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE-22

All CVSS Scores

CVSS v4.0 8.7 High

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS v3.1 7.5 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Researcher Blog

cve · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 19:20 UTC

    Public PoC available

    Public proof-of-concept code published

  2. 19:20 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  3. 19:00 UTC

    CVE published

    Vulnerability disclosed publicly

  4. 18:15 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2017-20284

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2017-20284",
  "confidence": "High",
  "cvss_score": 8.7,
  "cvss_estimated": false,
  "epss_score": 0.00958,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}