CVE-2020-27304

CRITICAL
Published Oct 21, 20214y ago · Modified Jun 17, 20261w ago
9.8 CVSS 3.1
Critical
Find Similar
Published Oct 21, 2021 4y ago
Last Modified Jun 17, 2026 1w ago

Description

The CivetWeb web library does not validate uploaded filepaths when running on an OS other than Windows, when using the built-in HTTP form-based file upload mechanism, via the mg_handle_form_request API. Web applications that use the file upload form handler, and use parts of the user-controlled filename in the output path, are susceptible to directory traversal

CVSS Details

Base Score
9.8
Exploitability
3.9
Impact
5.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

No active exploitation signals — not in CISA KEV and no EPSS score yet.

Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 2

CWE-22 Path Traversal Resource Mgmt
CWE-23

Affected Products 2

VendorProductVersionRange
civetweb_projectcivetweb*≥1.8  –  <1.15
siemenssinec_infrastructure_network_services* <1.0.1.1

References 4

  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf
  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
    PatchThird Party Advisory
  • groups.google.com https://groups.google.com/g/civetweb/c/yPBxNXdGgJQ
    Mailing ListThird Party Advisory
  • jfrog.com https://jfrog.com/blog/cve-2020-27304-rce-via-directory-traversal-in-civetweb-http-server/
    ExploitThird Party Advisory

Remediation