Paper/Archive/CVE-2026-68548

CVE-2026-68548

xyproto algernon — Algernon: Case-insensitive filesystem lets unauthenticated requests bypass /admin,/repo,/data permission-prefix gate

Description · from the CVE record

Algernon is a small self-contained pure-Go web server. Prior to version 1.17.10, Algernon's URL-prefix authorization gate matches its protected prefixes (/admin, /repo, /data) with case-sensitive strings.HasPrefix, while the exact same raw req.URL.Path is later resolved against the filesystem. On case-insensitive filesystems (Windows NTFS — always; macOS APFS/HFS+ — default), a request for /Admin/secret.lua evades every protected-prefix check, falls through to the public-prefix accept branch, and then resolves on disk to admin/secret.lua. The result is an unauthenticated bypass of the /admin, /repo, and /data authorization boundary, enabling read (and, for Lua files, execution) of protected content. The permission system is active in the default configuration. This issue has been patched in version 1.17.10.

Affected

ProductAffectedFixed inSource
algernon< 1.17.10–CNA

Scores by source

GitHub_M (CNA)9.4CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

References

refgithub.com/xyproto/algernon/security/advisories/GHSA-vm84-8c4p-64hxrefgithub.com/xyproto/algernon/releases/tag/v1.17.10