CVE-2026-34182

{"id": "CVE-2026-34182", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-34182", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-06-10T15:58:17.905043Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.1, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 3.9}]}, "affected": [{"source": "openssl-security@openssl.org", "affectedData": [{"vendor": "OpenSSL", "product": "OpenSSL", "versions": [{"status": "affected", "version": "4.0.0", "lessThan": "4.0.1", "versionType": "semver"}, {"status": "affected", "version": "3.6.0", "lessThan": "3.6.3", "versionType": "semver"}, {"status": "affected", "version": "3.5.0", "lessThan": "3.5.7", "versionType": "semver"}, {"status": "affected", "version": "3.4.0", "lessThan": "3.4.6", "versionType": "semver"}, {"status": "affected", "version": "3.0.0", "lessThan": "3.0.21", "versionType": "semver"}], "defaultStatus": "unaffected"}]}], "published": "2026-06-09T17:17:04.857", "references": [{"url": "https://github.com/openssl/openssl/commit/03c1f4d45fb963aee7d5833390c507cd290182bc", "tags": ["Patch"], "source": "openssl-security@openssl.org"}, {"url": "https://github.com/openssl/openssl/commit/439ed7d2c0962ce964482727264668bf277c333f", "tags": ["Patch"], "source": "openssl-security@openssl.org"}, {"url": "https://github.com/openssl/openssl/commit/7947e6a81eb8776802f159fb6762cb7fcf7e34c7", "tags": ["Patch"], "source": "openssl-security@openssl.org"}, {"url": "https://github.com/openssl/openssl/commit/9fd97f8cfdc2c0be214998de3b2b55c8edf6c7ac", "tags": ["Patch"], "source": "openssl-security@openssl.org"}, {"url": "https://github.com/openssl/openssl/commit/d2ca86bcd43e4f17d899f347101766b6107676e0", "tags": ["Patch"], "source": "openssl-security@openssl.org"}, {"url": "https://openssl-library.org/news/secadv/20260609.txt", "tags": ["Vendor Advisory"], "source": "openssl-security@openssl.org"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "openssl-security@openssl.org", "description": [{"lang": "en", "value": "CWE-354"}]}], "descriptions": [{"lang": "en", "value": "Issue Summary: Cryptographic Message Services (CMS) processing fails to perform\nsufficient input validation on the cipher and tag length fields of\nAuthEnvelopedData containers, leading to various potential compromises.\n\nImpact Summary: Attackers making use of these vulnerabilities may achieve\nkey-equivalent functionality for a given CMS recipient and/or bypass integrity\nvalidation for a given message.\n\nIn one use case, an attacker may send a CMS message containing\nAuthEnvelopedData with the cipher specified as a non-AEAD cipher. OpenSSL\nerroneously allows this selection, and attempts to decrypt and validate the\nmessage.\n\nAn on-path attacker who captures one legitimate AES-GCM AuthEnvelopedData\naddressed to the victim can re-emit it with the recipientInfos set left\nbyte-for-byte intact, so the victim's private key still unwraps the genuine CEK\n(the content-encryption key), but with the inner OID rewritten to AES-256-OFB\n(Output Feedback Mode, an unauthenticated keystream mode) and with an\nattacker-chosen IV and ciphertext. The victim initializes AES-256-OFB under the\nreal CEK, never consults the MAC field, and CMS_decrypt() returns success.\n\nIf the application under attack responds to the attacker with any indicator\nshowing success or failure of the decryption effort, it is possible for the\nattacker to use this as an oracle to obtain key equivalent functionality for the\nCEK used for the chosen recipient of the message.\n\nIn another use case, an attacker can reduce the tag length of the chosen AEAD\ncipher for a given AuthEnvelopedData container to be a single byte long,\nallowing an attacker to brute force CMS decryption, producing an integrity\nbypass for applications that trust CMS_decrypt() to reject modified content.\n\nThe FIPS modules are not affected by this issue."}, {"lang": "es", "value": "Resumen del problema: El procesamiento de los Servicios de Mensajes Criptogr\u00e1ficos (CMS) no realiza una validaci\u00f3n de entrada suficiente en los campos de cifrado y longitud de etiqueta de los contenedores AuthEnvelopedData, lo que lleva a varias posibles compromisos.\n\nResumen del impacto: Los atacantes que aprovechan estas vulnerabilidades pueden lograr una funcionalidad equivalente a la clave para un destinatario CMS dado y/o eludir la validaci\u00f3n de integridad para un mensaje dado.\n\nEn un caso de uso, un atacante puede enviar un mensaje CMS que contiene AuthEnvelopedData con el cifrado especificado como un cifrado no AEAD. OpenSSL permite err\u00f3neamente esta selecci\u00f3n e intenta descifrar y validar el mensaje.\n\nUn atacante en la ruta que captura un AuthEnvelopedData AES-GCM leg\u00edtimo dirigido a la v\u00edctima puede reemitirlo con el conjunto recipientInfos intacto byte a byte, de modo que la clave privada de la v\u00edctima a\u00fan desenvuelve la CEK genuina (la clave de cifrado de contenido), pero con el OID interno reescrito a AES-256-OFB (Modo de Retroalimentaci\u00f3n de Salida, un modo de flujo de clave no autenticado) y con un IV y texto cifrado elegidos por el atacante. La v\u00edctima inicializa AES-256-OFB bajo la CEK real, nunca consulta el campo MAC, y CMS_decrypt() devuelve \u00e9xito.\n\nSi la aplicaci\u00f3n bajo ataque responde al atacante con cualquier indicador que muestre el \u00e9xito o fracaso del esfuerzo de descifrado, es posible que el atacante use esto como un or\u00e1culo para obtener una funcionalidad equivalente a la clave para la CEK utilizada para el destinatario elegido del mensaje.\n\nEn otro caso de uso, un atacante puede reducir la longitud de la etiqueta del cifrado AEAD elegido para un contenedor AuthEnvelopedData dado a una longitud de un solo byte, permitiendo a un atacante forzar por fuerza bruta el descifrado CMS, produciendo una elusi\u00f3n de integridad para aplicaciones que conf\u00edan en que CMS_decrypt() rechace el contenido modificado.\n\nLos m\u00f3dulos FIPS no se ven afectados por este problema."}], "lastModified": "2026-07-23T08:10:00.137", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EDB88756-EDFE-4886-A267-3F19342A6042", "versionEndExcluding": "3.0.21", "versionStartIncluding": "3.0.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BF7E21E7-AEC0-4882-B1F1-2D056B506F22", "versionEndExcluding": "3.4.6", "versionStartIncluding": "3.4.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6B6B9930-C549-4D88-9784-AF32CCDDB87A", "versionEndExcluding": "3.5.7", "versionStartIncluding": "3.5.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D41B3C45-EC73-4DC8-989D-B2E2792E102F", "versionEndExcluding": "3.6.3", "versionStartIncluding": "3.6.0"}, {"criteria": "cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6E881B9A-1A0A-4BC0-8160-20C00561167D"}], "operator": "OR"}]}], "sourceIdentifier": "openssl-security@openssl.org"}