{
  "threat_severity" : "Moderate",
  "public_date" : "2026-07-22T19:19:42Z",
  "bugzilla" : {
    "description" : "thunderbird: Off-by-one out of bounds read in MIME header parser for forwarding",
    "id" : "2506217",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2506217"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.1",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
    "status" : "verified"
  },
  "cwe" : "CWE-125",
  "details" : [ "The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13.", "A flaw was found in Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:\nThe code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird." ],
  "statement" : "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-08-03T00:00:00Z",
    "advisory" : "RHSA-2026:49621",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "thunderbird-0:140.13.0-1.el10_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10.0 Extended Update Support",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53445",
    "cpe" : "cpe:/o:redhat:enterprise_linux_eus:10.0",
    "package" : "thunderbird-0:140.13.0-1.el10_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-08-04T00:00:00Z",
    "advisory" : "RHSA-2026:49922",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8",
    "package" : "thunderbird-0:140.13.0-1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53455",
    "cpe" : "cpe:/a:redhat:rhel_aus:8.4",
    "package" : "thunderbird-0:140.13.0-1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53455",
    "cpe" : "cpe:/a:redhat:rhel_eus_long_life:8.4",
    "package" : "thunderbird-0:140.13.0-1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53453",
    "cpe" : "cpe:/a:redhat:rhel_aus:8.6",
    "package" : "thunderbird-0:140.13.0-1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53453",
    "cpe" : "cpe:/a:redhat:rhel_eus_long_life:8.6",
    "package" : "thunderbird-0:140.13.0-1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53454",
    "cpe" : "cpe:/a:redhat:rhel_tus:8.8",
    "package" : "thunderbird-0:140.13.0-1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53454",
    "cpe" : "cpe:/a:redhat:rhel_e4s:8.8",
    "package" : "thunderbird-0:140.13.0-1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-08-04T00:00:00Z",
    "advisory" : "RHSA-2026:49921",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "thunderbird-0:140.13.0-1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53475",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.2",
    "package" : "thunderbird-0:140.13.0-1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53444",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.4",
    "package" : "thunderbird-0:140.13.0-1.el9_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.6 Extended Update Support",
    "release_date" : "2026-08-11T00:00:00Z",
    "advisory" : "RHSA-2026:53446",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.6",
    "package" : "thunderbird-0:140.13.0-1.el9_6"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Affected",
    "package_name" : "rhel10/thunderbird-flatpak",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "thunderbird",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "thunderbird",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-14899\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-14899\nhttps://www.mozilla.org/security/advisories/mfsa2026-72/#CVE-2026-14899" ],
  "name" : "CVE-2026-14899",
  "csaw" : false
}