{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-04-21T03:34:46.906","vulnerabilities":[{"cve":{"id":"CVE-2026-27468","sourceIdentifier":"security-advisories@github.com","published":"2026-02-24T18:29:33.660","lastModified":"2026-02-26T15:36:00.510","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"Mastodon is a free, open-source social network server based on ActivityPub. FASP registration requires manual approval by an administrator. In versions 4.4.0 through 4.4.13 and 4.5.0 through 4.5.6, actions performed by a FASP to subscribe to account/content lifecycle events or to backfill content did not check properly whether the FASP was actually approved. This only affects Mastodon servers that have opted in to testing the experimental FASP feature by setting the environment variable `EXPERIMENTAL_FEATURES` to a value including `fasp`. An attacker can make subscriptions and request content backfill without approval by an administrator. Done once, this leads to minor information leak of URIs that are publicly available anyway. But done several times this is a serious vector for DOS, putting pressure on the sidekiq worker responsible for the `fasp` queue. The fix is included in the 4.4.14 and 4.5.7 releases. Admins that are actively testing the experimental \"fasp\" feature should update their systems. Servers not using the experimental feature flag `fasp` are not affected."},{"lang":"es","value":"Mastodon es un servidor de red social gratuito y de código abierto basado en ActivityPub. El registro FASP requiere aprobación manual por parte de un administrador. En las versiones 4.4.0 a 4.4.13 y 4.5.0 a 4.5.6, las acciones realizadas por un FASP para suscribirse a eventos del ciclo de vida de cuentas/contenido o para rellenar contenido (backfill) no verificaban correctamente si el FASP estaba realmente aprobado. Esto solo afecta a los servidores de Mastodon que han optado por probar la característica experimental FASP configurando la variable de entorno 'EXPERIMENTAL_FEATURES' con un valor que incluya 'fasp'. Un atacante puede realizar suscripciones y solicitar el rellenado de contenido (backfill) sin la aprobación de un administrador. Hecho una vez, esto conduce a una fuga menor de información de URIs que de todos modos están disponibles públicamente. Pero hecho varias veces, esto es un vector serio para DoS, ejerciendo presión sobre el worker de sidekiq responsable de la cola 'fasp'. La solución está incluida en las versiones 4.4.14 y 4.5.7. Los administradores que están probando activamente la característica experimental 'fasp' deberían actualizar sus sistemas. Los servidores que no utilizan la bandera de característica experimental 'fasp' no se ven afectados."}],"metrics":{"cvssMetricV40":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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","baseScore":4.8,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"UNREPORTED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H","baseScore":8.2,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":4.2}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Primary","description":[{"lang":"en","value":"CWE-862"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4.0","versionEndExcluding":"4.4.14","matchCriteriaId":"F8A96B12-8C08-4A0C-88A8-B7B2B7AED3BF"},{"vulnerable":true,"criteria":"cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*","versionStartIncluding":"4.5.0","versionEndExcluding":"4.5.7","matchCriteriaId":"65E9009A-6D3F-4758-8EAA-6D832F06F3F6"}]}]}],"references":[{"url":"https://github.com/mastodon/mastodon/commit/6ba6285a73c3a8b281123814d45f534e3bcebb96","source":"security-advisories@github.com","tags":["Patch"]},{"url":"https://github.com/mastodon/mastodon/security/advisories/GHSA-qgmm-vr4c-ggjg","source":"security-advisories@github.com","tags":["Vendor Advisory","Patch"]}]}}]}