{"id":"CVE-2026-49819","state":"PUBLISHED","title":"UpSnap - Unauthenticated Initial-Superuser Takeover Chains to Root RCE via wake_cmd","description":"UpSnap is a wake on lan web app. Versions 4.4.1 through 5.3.5 are vulnerable to a missing-authentication / privilege-escalation chain in `pb.HandlerInitSuperuser` (`backend/pb/handlers.go:249`), reachable as `POST /api/upsnap/init-superuser`. The vulnerable code lacks any authentication, setup token, IP allow-list, or rate limit and is gated only by a `totalSuperusers > 0` count check — a condition that is false on every fresh install — allowing an unauthenticated network-adjacent attacker to register the initial superuser account, receive a long-lived JWT, and pivot to root remote code execution at `backend/networking/wake.go:43` (`exec.CommandContext(ctx, \"/bin/sh\", \"-c\", wake_cmd)`). Version 5.4.0 fixes the issue.","publishedAt":"2026-08-12T23:13:46.298Z","updatedAt":"2026-08-13T13:08:59.003Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["seriousm4x UpSnap"],"affected":[{"vendor":"seriousm4x","product":"UpSnap","versions":[{"version":">= 4.4.1, < 5.4.0","status":"affected"}]}],"references":["https://github.com/seriousm4x/UpSnap/security/advisories/GHSA-w4jr-728f-5jhq","https://github.com/seriousm4x/UpSnap/releases/tag/5.4.0"],"weaknesses":["CWE-78","CWE-269","CWE-306","CWE-862"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/49xxx/CVE-2026-49819.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-49819","state":"PUBLISHED","datePublished":"2026-08-12T23:13:46.298Z","dateUpdated":"2026-08-13T13:08:59.003Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-01T18:50:36.055Z"},"containers":{"cna":{"title":"UpSnap - Unauthenticated Initial-Superuser Takeover Chains to Root RCE via wake_cmd","descriptions":[{"lang":"en","value":"UpSnap is a wake on lan web app. Versions 4.4.1 through 5.3.5 are vulnerable to a missing-authentication / privilege-escalation chain in `pb.HandlerInitSuperuser` (`backend/pb/handlers.go:249`), reachable as `POST /api/upsnap/init-superuser`. The vulnerable code lacks any authentication, setup token, IP allow-list, or rate limit and is gated only by a `totalSuperusers > 0` count check — a condition that is false on every fresh install — allowing an unauthenticated network-adjacent attacker to register the initial superuser account, receive a long-lived JWT, and pivot to root remote code execution at `backend/networking/wake.go:43` (`exec.CommandContext(ctx, \"/bin/sh\", \"-c\", wake_cmd)`). Version 5.4.0 fixes the issue."}],"affected":[{"vendor":"seriousm4x","product":"UpSnap","versions":[{"version":">= 4.4.1, < 5.4.0","status":"affected"}]}],"references":[{"url":"https://github.com/seriousm4x/UpSnap/security/advisories/GHSA-w4jr-728f-5jhq","name":"https://github.com/seriousm4x/UpSnap/security/advisories/GHSA-w4jr-728f-5jhq","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/seriousm4x/UpSnap/releases/tag/5.4.0","name":"https://github.com/seriousm4x/UpSnap/releases/tag/5.4.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":9.8,"baseSeverity":"CRITICAL","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-78","lang":"en","description":"CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-269","lang":"en","description":"CWE-269: Improper Privilege Management","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-306","lang":"en","description":"CWE-306: Missing Authentication for Critical Function","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-862","lang":"en","description":"CWE-862: Missing Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-12T23:13:46.298Z"},"source":{"advisory":"GHSA-w4jr-728f-5jhq","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/seriousm4x/UpSnap/security/advisories/GHSA-w4jr-728f-5jhq","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-13T13:08:41.648461Z","id":"CVE-2026-49819","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-13T13:08:59.003Z"}}]}}}