{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.17.6"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "60bb98841972ffd6a3a32a4cde18517fae0ea2ef"
            }
          ],
          "repo": "https://github.com/xyproto/algernon",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-rr2f-4wrm-h6rg"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-362"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43981.json"
  },
  "details": "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.",
  "id": "CVE-2026-43981",
  "modified": "2026-07-08T05:39:00.274860802Z",
  "published": "2026-05-26T16:31:55.696Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43981.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/xyproto/algernon/security/advisories/GHSA-rr2f-4wrm-h6rg"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43981"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/xyproto/algernon/issues/172"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Algernon: Race Condition in handle() shared LState"
}