CivetwebApplication · Civetweb Project

CVE-2020-27304

CRITICAL · 9.8 CVSS v3.1 Published 2021-10-21
Fix available
A fix is available. Upgrade to 1.0.1.1 / 1.15 or later.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
CivetwebApplication
Affected:>= 1.8, < 1.15
Sinec Infrastructure Network ServicesApplication
Affected:< 1.0.1.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.0.1.1 / 1.15 or later
Fixed in 1.0.1.11.15
Recommended fix High confidence

CivetWeb >= 1.15 | Sinec Infrastructure Network Services >= 1.0.1.1

  1. For CivetWeb: Upgrade to version 1.15 or later, which includes the filepath validation fix
  2. For Sinec Infrastructure Network Services: Upgrade to version 1.0.1.1 or later which incorporates the patch from vendor advisory SSA-389290
  3. If upgrading is not immediately possible, implement input validation on the server-side to sanitize user-supplied filename parameters in file upload handlers, rejecting any path traversal sequences (such as '../' or '..\') before processing the upload

Generated from the published advisory — verify against the referenced sources before acting.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-27304 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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