CVE-2026-43981

Algernon is a small self-contained pure-Go web server. Prior to 1.17.6, in engine/luahandler.go, the sync.RWMutex protecting LoadCommonFunctions is released before L.Push() and L.PCall() execute. Since gopher-lua's LState is explicitly not goroutine-safe, concurrent requests race on the shared state causing Lua VM corruption. The Go race detector confirms this immediately under modest concurrency (ab -n 1000 -c 100). This vulnerability is fixed in 1.17.6.

CVSS

No CVSS.

References

Link	Resource
https://github.com/xyproto/algernon/issues/172
https://github.com/xyproto/algernon/security/advisories/GHSA-rr2f-4wrm-h6rg

Configurations

No configuration.

History

26 May 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-26 17:16

Updated : 2026-05-26 19:26

NVD link : CVE-2026-43981

Mitre link : CVE-2026-43981

CVE.ORG link : CVE-2026-43981

JSON object : View

Products Affected

No product.

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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