{ "threat_severity" : "Moderate", "public_date" : "2026-06-09T00:00:00Z", "bugzilla" : { "description" : "openssl: CMS AuthEnvelopedData Processing May Accept Forged Messages", "id" : "2481884", "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2481884" }, "cvss3" : { "cvss3_base_score" : "7.4", "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N", "status" : "verified" }, "cwe" : "CWE-130", "details" : [ "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.\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.\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.\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.\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.\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.\nThe FIPS modules are not affected by this issue.", "A flaw was found in OpenSSL's Cryptographic Message Services (CMS) AuthEnvelopedData processing. An on-path attacker can exploit insufficient input validation on cipher and tag length fields by sending specially crafted CMS messages. This can lead to the forging of messages or bypassing integrity validation. Consequently, an attacker may achieve key-equivalent functionality for a given CMS recipient." ], "statement" : "Moderate: This flaw in OpenSSL's Cryptographic Message Services (CMS) AuthEnvelopedData processing could allow an on-path attacker to forge messages or bypass integrity validation. This is due to insufficient input validation on cipher and tag length fields, potentially leading to key-equivalent functionality or integrity bypass in applications utilizing affected OpenSSL versions for CMS AuthEnvelopedData.", "affected_release" : [ { "product_name" : "Red Hat Enterprise Linux 10", "release_date" : "2026-06-11T00:00:00Z", "advisory" : "RHSA-2026:25237", "cpe" : "cpe:/o:redhat:enterprise_linux:10.2", "package" : "openssl-1:3.5.5-4.el10_2" }, { "product_name" : "Red Hat Enterprise Linux 9", "release_date" : "2026-06-11T00:00:00Z", "advisory" : "RHSA-2026:25239", "cpe" : "cpe:/a:redhat:enterprise_linux:9", "package" : "openssl-1:3.5.5-4.el9_8" }, { "product_name" : "Red Hat Enterprise Linux 9", "release_date" : "2026-06-11T00:00:00Z", "advisory" : "RHSA-2026:25239", "cpe" : "cpe:/o:redhat:enterprise_linux:9", "package" : "openssl-1:3.5.5-4.el9_8" }, { "product_name" : "Red Hat Update Infrastructure 5", "release_date" : "2026-06-16T00:00:00Z", "advisory" : "RHSA-2026:26319", "cpe" : "cpe:/a:redhat:rhui:5::el9", "package" : "rhui5/cds-rhel9:1781525684" }, { "product_name" : "Red Hat Update Infrastructure 5", "release_date" : "2026-06-16T00:00:00Z", "advisory" : "RHSA-2026:26319", "cpe" : "cpe:/a:redhat:rhui:5::el9", "package" : "rhui5/haproxy-rhel9:1781525671" }, { "product_name" : "Red Hat Update Infrastructure 5", "release_date" : "2026-06-16T00:00:00Z", "advisory" : "RHSA-2026:26319", "cpe" : "cpe:/a:redhat:rhui:5::el9", "package" : "rhui5/installer-rhel9:1781525693" }, { "product_name" : "Red Hat Update Infrastructure 5", "release_date" : "2026-06-16T00:00:00Z", "advisory" : "RHSA-2026:26319", "cpe" : "cpe:/a:redhat:rhui:5::el9", "package" : "rhui5/rhua-rhel9:1781525739" } ], "package_state" : [ { "product_name" : "Red Hat Enterprise Linux 10", "fix_state" : "Not affected", "package_name" : "edk2", "cpe" : "cpe:/o:redhat:enterprise_linux:10" }, { "product_name" : "Red Hat Enterprise Linux 10", "fix_state" : "Not affected", "package_name" : "shim", "cpe" : "cpe:/o:redhat:enterprise_linux:10" }, { "product_name" : "Red Hat Enterprise Linux 10", "fix_state" : "Not affected", "package_name" : "shim-unsigned-aarch64", "cpe" : "cpe:/o:redhat:enterprise_linux:10" }, { "product_name" : "Red Hat Enterprise Linux 10", "fix_state" : "Not affected", "package_name" : "shim-unsigned-x64", "cpe" : "cpe:/o:redhat:enterprise_linux:10" }, { "product_name" : "Red Hat Enterprise Linux 6", "fix_state" : "Not affected", "package_name" : "openssl", "cpe" : "cpe:/o:redhat:enterprise_linux:6" }, { "product_name" : "Red Hat Enterprise Linux 7", "fix_state" : "Not affected", "package_name" : "ovmf", "cpe" : "cpe:/o:redhat:enterprise_linux:7" }, { "product_name" : "Red Hat Enterprise Linux 8", "fix_state" : "Not affected", "package_name" : "compat-openssl10", "cpe" : "cpe:/o:redhat:enterprise_linux:8" }, { "product_name" : "Red Hat Enterprise Linux 8", "fix_state" : "Not affected", "package_name" : "edk2", "cpe" : "cpe:/o:redhat:enterprise_linux:8" }, { "product_name" : "Red Hat Enterprise Linux 8", "fix_state" : "Not affected", "package_name" : "mingw-openssl", "cpe" : "cpe:/o:redhat:enterprise_linux:8" }, { "product_name" : "Red Hat Enterprise Linux 8", "fix_state" : "Affected", "package_name" : "openssl", "cpe" : "cpe:/o:redhat:enterprise_linux:8" }, { "product_name" : "Red Hat Enterprise Linux 8", "fix_state" : "Not affected", "package_name" : "shim", "cpe" : "cpe:/o:redhat:enterprise_linux:8" }, { "product_name" : "Red Hat Enterprise Linux 8", "fix_state" : "Not affected", "package_name" : "shim-unsigned-x64", "cpe" : "cpe:/o:redhat:enterprise_linux:8" }, { "product_name" : "Red Hat Enterprise Linux 9", "fix_state" : "Not affected", "package_name" : "compat-openssl11", "cpe" : "cpe:/o:redhat:enterprise_linux:9" }, { "product_name" : "Red Hat Enterprise Linux 9", "fix_state" : "Not affected", "package_name" : "edk2", "cpe" : "cpe:/o:redhat:enterprise_linux:9" }, { "product_name" : "Red Hat Enterprise Linux 9", "fix_state" : "Not affected", "package_name" : "shim", "cpe" : "cpe:/o:redhat:enterprise_linux:9" }, { "product_name" : "Red Hat Enterprise Linux 9", "fix_state" : "Not affected", "package_name" : "shim-unsigned-aarch64", "cpe" : "cpe:/o:redhat:enterprise_linux:9" }, { "product_name" : "Red Hat Enterprise Linux 9", "fix_state" : "Not affected", "package_name" : "shim-unsigned-x64", "cpe" : "cpe:/o:redhat:enterprise_linux:9" }, { "product_name" : "Red Hat OpenShift Container Platform 4", "fix_state" : "Affected", "package_name" : "rhcos", "cpe" : "cpe:/a:redhat:openshift:4" } ], "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-34182\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-34182" ], "name" : "CVE-2026-34182", "mitigation" : { "value" : "Systems configured to operate in FIPS mode are not affected by this vulnerability. To mitigate this issue, ensure that OpenSSL is operating in FIPS mode by enabling the system-wide FIPS policy. This may have broader implications for cryptographic operations on the system and should be evaluated for compatibility with existing applications. A system reboot may be required for the changes to take effect.", "lang" : "en:us" }, "csaw" : false }