{
  "threat_severity" : "Low",
  "public_date" : "2026-06-09T00:00:00Z",
  "bugzilla" : {
    "description" : "openssl: OpenSSL: Denial of Service due to heap out-of-bounds read in CMS password-based decryption",
    "id" : "2481880",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2481880"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.9",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-131",
  "details" : [ "Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap)\nprocesses attacker-supplied CMS data, an attacker-chosen stream-mode KEK\ncipher can trigger a heap out-of-bounds read in kek_unwrap_key().\nImpact summary: A heap buffer over-read may trigger a crash which leads to\nDenial of Service for an application if the input buffer ends at a memory\npage boundary and the following page is unmapped. There is no information\ndisclosure as the over-read bytes are not revealed to the attacker.\nThe key unwrapping function performs a check-byte test as specified in the\nRFC that reads 7 bytes from a heap allocation that is based on the wrapped\nkey length from the message. There is a minimum length check based on the\nblock length of the wrapping cipher. However the cipher is selected from\nan OID carried in the attacker's PWRI keyEncryptionAlgorithm with no\nrequirement that the cipher be a block cipher. When an attacker selects\na stream-mode cipher the guard will be ineffective and the allocated buffer\ncontaining the unwrapped key can be too small to fit the check-bytes\nspecified in the RFC and a buffer over-read can happen.\nApplications calling CMS_decrypt() or CMS_decrypt_set1_password()\n(equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS\ndata are vulnerable to this issue. No password knowledge is required: the\nover-read happens during the unwrap attempt before any authentication\nsucceeds.\nThe over-read is limited to a few bytes and is not written to output, so\nthere is no information disclosure. Triggering a crash requires the\nallocation to border unmapped memory, which is unlikely with the normal\nallocator.\nThe FIPS modules are not affected by this issue.", "A flaw was found in OpenSSL. When processing attacker-supplied Cryptographic Message Syntax (CMS) data using password-based decryption, an attacker can choose a stream-mode Key Encryption Key (KEK) cipher. This can trigger a heap out-of-bounds read, potentially causing an application crash and leading to a Denial of Service (DoS). This vulnerability does not require password knowledge and can be exploited before authentication." ],
  "statement" : "This is a Low impact denial of service due to a heap out-of-bounds read in `kek_unwrap_key()` when processing attacker-supplied CMS data with an attacker-chosen stream-mode KEK cipher. This flaw requires specific memory conditions (input buffer ending at a page boundary with an unmapped following page) to trigger a crash, which is uncommon in typical Red Hat environments. No information disclosure is possible, and FIPS modules are not affected.",
  "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-2026-9076\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-9076" ],
  "name" : "CVE-2026-9076",
  "mitigation" : {
    "value" : "Mitigation 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
}