Critical severity · published Oct 21, 2021
CVE-2020-27304
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…
9.8
CVSS
3.2%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CI
Civetweb · Civetweb Project
1.8 before 1.15 · source: NVD
SI
Sinec Infrastructure Network Services · Siemens
before 1.0.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-27304
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-27304
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf
Patch
https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
Mailing List
https://groups.google.com/g/civetweb/c/yPBxNXdGgJQ
Exploit
https://jfrog.com/blog/cve-2020-27304-rce-via-directory-traversal-in-civetweb-http-server/
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