{"id":"CVE-2026-38821","details":"A heap-based buffer overflow vulnerability exists in openNDS before 11.0.0 that allows an unauthenticated attacker on the captive portal network to crash the openNDS daemon (denial of service) and potentially achieve remote code execution. This is in http_microhttpd.c.","modified":"2026-08-30T08:17:16.220227Z","published":"2026-08-28T00:10:10.769Z","database_specific":{"cna_assigner":"mitre","cwe_ids":["CWE-122"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/38xxx/CVE-2026-38821.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/38xxx/CVE-2026-38821.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-38821"},{"type":"FIX","url":"https://github.com/openNDS/openNDS/commit/3b5f7ef40cd048826d3c4a16f61a73a1768fd5a9"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/opennds/opennds","events":[{"introduced":"0"},{"fixed":"9477b224bfd6d7f27ab1f1931afb61580b9470d1"},{"fixed":"3b5f7ef40cd048826d3c4a16f61a73a1768fd5a9"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"11.0.0"}],"source":["DESCRIPTION","REFERENCES"]}}],"versions":["v10.3.1","v10.3.0","v10.2.0","v10.1.3","v10.1.2","v10.1.1","v10.1.0","v9.10.0","v9.9.1","v9.9.0","v9.8.0","v9.7.0","v9.6.0","v9.5.1","v9.5.0","v9.4.0","v9.3.0","v9.2.0","v9.1.1","v9.1.0","v9.0.0","v8.1.1","v8.1.0","v8.0.0","v7.0.1","v7.0.0","v6.0.0","v5.2.0","v5.1.0","v5.0.1","v5.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-38821.json","vanir_signatures_modified":"2026-08-30T08:17:16Z","vanir_signatures":[{"source":"https://github.com/opennds/opennds/commit/3b5f7ef40cd048826d3c4a16f61a73a1768fd5a9","target":{"function":"redirect_to_splashpage","file":"src/http_microhttpd.c"},"deprecated":false,"digest":{"function_hash":"311421305056004275875715927435170307547","length":1446},"id":"CVE-2026-38821-1031677f","signature_type":"Function","signature_version":"v1"},{"signature_version":"v1","source":"https://github.com/opennds/opennds/commit/3b5f7ef40cd048826d3c4a16f61a73a1768fd5a9","target":{"file":"src/http_microhttpd.c"},"deprecated":false,"digest":{"threshold":0.9,"line_hashes":["104120432630675651287375848698660759807","333119376069059100285092984272616262566","77823246634169758154534252860526279576","195099720023997218876787609873204965919"]},"id":"CVE-2026-38821-a6253985","signature_type":"Line"}]}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L"}]}