{
  "threat_severity" : "Low",
  "public_date" : "2026-06-09T00:00:00Z",
  "bugzilla" : {
    "description" : "openssl: Incorrect Tag Processing for Empty Messages in AES-GCM-SIV and AES-SIV modes",
    "id" : "2481897",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2481897"
  },
  "cvss3" : {
    "cvss3_base_score" : "3.7",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
    "status" : "verified"
  },
  "cwe" : "CWE-347",
  "details" : [ "Issue summary: The implementations of AES-SIV (RFC 5297) and AES-GCM-SIV\n(RFC 8452) mishandle the authentication of AAD (Additional Authenticated\nData) with an empty ciphertext allowing a forgery of such messages.\nImpact summary: An attacker can forge empty messages with arbitrary AAD\nto the victim's application using these ciphers.\nAES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) are nonce-misuse-resistant AEAD\nmodes: they accept a key, nonce, optional AAD (bytes that are authenticated\nbut not encrypted), and plaintext, and produces ciphertext plus a 16-byte\ntag. On decrypt, `EVP_DecryptFinal_ex()` is documented to return success only\nif the tag is verified succesfully.\nIn OpenSSL's provider implementation of these ciphers, the expected tag is\ncomputed only when decryption function is invoked with non-empty data.\nIf the caller supplies AAD and then calls `EVP_DecryptFinal_ex()` without\ninvocation of the ciphertext update, which can happen when the received\nciphertext length is zero, the tag is never recalculated and still holds its\nall-zeros value.\nWhen AES-GCM-SIV is used, an attacker who sends arbitrary AAD, empty\nciphertext, and all-zeros tag passes authentication under any key they do not\nknow, single-shot. When AES-SIV is used, for mounting the attack it's\nnecessary for the application to reuse the decryption context without\nresetting the key.\nAES-SIV is implemented since OpenSSL 3.0. AES-GCM-SIV is implemented since\nOpenSSL 3.2.\nNo protocols implemented in OpenSSL itself (TLS/CMS/PKCS7/HPKE/QUIC) support\neither AES-GCM-SIV or AES-SIV. To mount an attack, the applications must\nimplement their own protocol and use the EVP interface. Also they must skip the\nciphertext update when a message with an empty ciphertext arrives.\nThe FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this\nissue, as these algorithms are not FIPS approved and the affected code is\noutside the OpenSSL FIPS module boundary.", "A flaw was found in OpenSSL. The implementations of AES-SIV (Advanced Encryption Standard - SIV) and AES-GCM-SIV (Advanced Encryption Standard - Galois/Counter Mode - SIV) incorrectly process authentication tags for empty messages. This vulnerability allows a remote attacker to forge empty messages with arbitrary Additional Authenticated Data (AAD) in applications that utilize these specific cipher modes within custom protocols and do not properly handle zero-length ciphertexts. This could lead to unauthorized data manipulation." ],
  "statement" : "This flaw is rated as Low impact. It affects applications that utilize OpenSSL's AES-SIV or AES-GCM-SIV modes within custom protocols and specifically mishandle empty ciphertexts. Standard OpenSSL protocols, such as TLS, are not affected. Successful exploitation requires an application to use the EVP interface and to skip ciphertext updates when processing zero-length ciphertexts, representing an uncommon and non-default configuration.",
  "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" : "Fix deferred",
    "package_name" : "edk2",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "shim",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "shim-unsigned-aarch64",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "shim-unsigned-x64",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Fix deferred",
    "package_name" : "openssl",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "ovmf",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "compat-openssl10",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "edk2",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "mingw-openssl",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "openssl",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "shim",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "shim-unsigned-x64",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "compat-openssl11",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "edk2",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "shim",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "shim-unsigned-aarch64",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "shim-unsigned-x64",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4",
    "fix_state" : "Fix deferred",
    "package_name" : "rhcos",
    "cpe" : "cpe:/a:redhat:openshift:4"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-45446\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-45446" ],
  "name" : "CVE-2026-45446",
  "mitigation" : {
    "value" : "The vulnerability arises from specific application implementations using OpenSSL's AES-SIV or AES-GCM-SIV modes with custom protocols and an atypical handling of empty ciphertexts. As this scenario is not a default or commonly deployed configuration in Red Hat products, and no direct configuration or operational control exists to mitigate this specific flaw without patching, the following applies:\nMitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.",
    "lang" : "en:us"
  },
  "csaw" : false
}