CVE-2026-52792

Algernon is a small self-contained pure-Go web server. Prior to 1.17.9, Algernon on Windows selects a file handler in engine/handlers.go by calling filepath.Ext() without first rejecting NTFS-equivalent names such as x.lua::$DATA, x.lua., and x.lua . An unauthenticated client can append one of these suffixes to a public server-side script using the .lua, .tl, .po2, .amber, or .frm extension. The request path passes through URL2filename in utils/files.go, skips the renderer and execution cases, and reaches FilePage, os.Open, ReadAndLogErrors, and ToClient, while NTFS resolves the alias to the underlying script. The server consequently returns raw script source and can expose database credentials, API keys, and the SetCookieSecret value, which may permit forged session cookies. Linux and macOS hosts are not affected by this issue. This issue is fixed in version 1.17.9.

CVSS

No CVSS.

References

Link	Resource
https://github.com/xyproto/algernon/commit/a6b0724928a0c35a29640b18ad5bd547f5e2efa6
https://github.com/xyproto/algernon/releases/tag/v1.17.9
https://github.com/xyproto/algernon/security/advisories/GHSA-mm6c-5j6x-hq8m
https://github.com/xyproto/algernon/security/advisories/GHSA-mm6c-5j6x-hq8m

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 15:17

Updated : 2026-08-19 16:17

NVD link : CVE-2026-52792

Mitre link : CVE-2026-52792

CVE.ORG link : CVE-2026-52792

JSON object : View

Products Affected

No product.

CWE

CWE-69

Improper Handling of Windows ::DATA Alternate Data Stream

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