CVE intelligence and bounded remediation
CVE-2021-27964 — SonLogger before 6.4.1 is affected by Unauthenticated Arbitrary File Upload
Critical
CVSS 9.8
SonLogger before 6.4.1 is affected by Unauthenticated Arbitrary File Upload. An attacker can send a POST request to /Config/SaveUploadedHotspotLogoFile without any authentication or session header. There is no check for the file extension or content of the uploaded file.
- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Published
- 2021-03-05
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-434
Affected products
- sfcyazilim / sonlogger
Matched remediation archetype
Path traversal, unsafe upload, and file handling
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Check exposure
- Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
- Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
- Review canonicalization and containment checks across supported operating systems and storage backends.
Remediate safely
- Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
- Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
- Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.
Authoritative sources
Complete CVE record and remediation plan
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