CVE-2026-43982
High
Description
Algernon is a small self-contained pure-Go web server. Prior to 1.17.6, uploadedFileSaveIn() in lua/upload/upload.go uses filepath.Join() with the caller-supplied directory but performs no boundary check after joining. A directory of ../../../tmp resolves cleanly to /tmp, outside the web root. This vulnerability is fixed in 1.17.6.
SeverityHigh
CVSS8.7
Exploit probability—
ProductXyproto Algernon
PublishedMay 26, 2026
First seenMay 26, 2026
Weakness typeCWE-22Path traversal
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| xyproto algernon | < 1.17.6 | — |
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