CVE-2026-72861

{"id": "CVE-2026-72861", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-72861", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-21T21:33:32.540767Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 5.8, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.9, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "LOW", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"repo": "https://github.com/appwrite/templates", "vendor": "appwrite", "product": "templates", "versions": [{"status": "affected", "version": "0", "versionType": "semver", "lessThanOrEqual": "1.1.2"}], "programFiles": ["node/github-issue-bot/src/github.js", "node-typescript/github-issue-bot/src/github.ts"], "defaultStatus": "unaffected"}]}], "published": "2026-08-20T20:17:46.190", "references": [{"url": "https://github.com/appwrite/templates", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/appwrite/templates/blob/1.1.2/node-typescript/github-issue-bot/src/github.ts", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/appwrite/templates/blob/1.1.2/node/github-issue-bot/src/github.js", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/appwrite/templates/blob/1.1.2/node/github-issue-bot/src/main.js", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/appwrite/templates/issues/350", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/appwrite-templates-github-issue-bot-skips-webhook-signature-verification-when-the-x-hub-signature-256-header-is-absent", "source": "disclosure@vulncheck.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-347"}]}], "descriptions": [{"lang": "en", "value": "The github-issue-bot templates in appwrite/templates verify the GitHub webhook signature with an inverted condition. verifyWebhook in node/github-issue-bot/src/github.js and in node-typescript/github-issue-bot/src/github.ts returns \"typeof signature !== 'string' || (await verify(...))\", so when the X-Hub-Signature-256 header is absent the first operand is true, the logical OR short-circuits, and the function reports success without performing any HMAC verification. main.js rejects a request only when verifyWebhook returns false, so an unauthenticated request carrying no signature passes the check. Processing then continues to postComment, which takes the repository and issue objects directly from the request body, letting the caller direct the deployed function to post a comment on a repository and issue of their choosing using the configured GITHUB_TOKEN, with the issue author login from the body interpolated into the comment text."}, {"lang": "es", "value": "Las plantillas de github-issue-bot en appwrite/templates verifican la firma del webhook de GitHub con una condici\u00f3n invertida. verifyWebhook en node/github-issue-bot/src/github.js y en node-typescript/github-issue-bot/src/github.ts devuelve 'typeof signature !== 'string' || (await verify(...))', por lo que cuando el encabezado X-Hub-Signature-256 est\u00e1 ausente, el primer operando es verdadero, el OR l\u00f3gico realiza un cortocircuito y la funci\u00f3n informa \u00e9xito sin realizar ninguna verificaci\u00f3n HMAC. main.js rechaza una solicitud solo cuando verifyWebhook devuelve falso, por lo que una solicitud no autenticada que no lleva firma pasa la verificaci\u00f3n. El procesamiento luego contin\u00faa a postComment, que toma los objetos de repositorio y de incidencia directamente del cuerpo de la solicitud, permitiendo al llamador dirigir la funci\u00f3n desplegada para publicar un comentario en un repositorio y una incidencia de su elecci\u00f3n usando el GITHUB_TOKEN configurado, con el login del autor de la incidencia del cuerpo interpolado en el texto del comentario."}], "lastModified": "2026-10-18T20:10:00.110", "sourceIdentifier": "disclosure@vulncheck.com"}