ALSA-2026:21381 (CVE-2026-8388)

Vulnerability from osv_almalinux – Published: 2026-05-27 00:00 – Updated: 2026-05-29 09:48 – Source website
VLAI
Summary
Important: thunderbird security update
Details

Mozilla Thunderbird is a standalone mail and newsgroup client.

Security Fix(es):

  • firefox: Incorrect boundary conditions in the JavaScript Engine: JIT component (CVE-2026-8388)
  • firefox: Other issue in the JavaScript Engine component (CVE-2026-8391)
  • firefox: Sandbox escape in the Profile Backup component (CVE-2026-8401)
  • firefox: Integer overflow in the Networking: JAR component (CVE-2026-8956)
  • firefox: Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151 (CVE-2026-8975)
  • firefox: Privilege escalation in the DOM: Workers component (CVE-2026-8955)
  • firefox: Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component (CVE-2026-8968)
  • firefox: Incorrect boundary conditions, integer overflow in the Audio/Video component (CVE-2026-8954)
  • firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component (CVE-2026-8958)
  • firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component (CVE-2026-8946)
  • firefox: Privilege escalation in the Security component (CVE-2026-8970)
  • firefox: Same-origin policy bypass in the Networking: HTTP component (CVE-2026-8950)
  • firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151 (CVE-2026-8974)
  • firefox: Sandbox escape due to use-after-free in the Disability Access APIs component (CVE-2026-8953)
  • firefox: Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component (CVE-2026-8959)
  • firefox: Spoofing issue in the Form Autofill component (CVE-2026-8961)
  • firefox: Use-after-free in the DOM: Bindings (WebIDL) component (CVE-2026-8947)
  • firefox: Mitigation bypass in the DOM: Security component (CVE-2026-8962)
  • firefox: Privilege escalation in the Enterprise Policies component (CVE-2026-8957)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

References
https://access.redhat.com/errata/RHSA-2026:21381 ADVISORY
https://access.redhat.com/security/cve/CVE-2026-8388 REPORT
https://access.redhat.com/security/cve/CVE-2026-8391 REPORT
https://access.redhat.com/security/cve/CVE-2026-8401 REPORT
https://access.redhat.com/security/cve/CVE-2026-8946 REPORT
https://access.redhat.com/security/cve/CVE-2026-8947 REPORT
https://access.redhat.com/security/cve/CVE-2026-8950 REPORT
https://access.redhat.com/security/cve/CVE-2026-8953 REPORT
https://access.redhat.com/security/cve/CVE-2026-8954 REPORT
https://access.redhat.com/security/cve/CVE-2026-8955 REPORT
https://access.redhat.com/security/cve/CVE-2026-8956 REPORT
https://access.redhat.com/security/cve/CVE-2026-8957 REPORT
https://access.redhat.com/security/cve/CVE-2026-8958 REPORT
https://access.redhat.com/security/cve/CVE-2026-8959 REPORT
https://access.redhat.com/security/cve/CVE-2026-8961 REPORT
https://access.redhat.com/security/cve/CVE-2026-8962 REPORT
https://access.redhat.com/security/cve/CVE-2026-8968 REPORT
https://access.redhat.com/security/cve/CVE-2026-8970 REPORT
https://access.redhat.com/security/cve/CVE-2026-8974 REPORT
https://access.redhat.com/security/cve/CVE-2026-8975 REPORT
https://bugzilla.redhat.com/2476469 REPORT
https://bugzilla.redhat.com/2476475 REPORT
https://bugzilla.redhat.com/2476492 REPORT
https://bugzilla.redhat.com/2479839 REPORT
https://bugzilla.redhat.com/2479840 REPORT
https://bugzilla.redhat.com/2479842 REPORT
https://bugzilla.redhat.com/2479846 REPORT
https://bugzilla.redhat.com/2479847 REPORT
https://bugzilla.redhat.com/2479848 REPORT
https://bugzilla.redhat.com/2479849 REPORT
https://bugzilla.redhat.com/2479852 REPORT
https://bugzilla.redhat.com/2479853 REPORT
https://bugzilla.redhat.com/2479855 REPORT
https://bugzilla.redhat.com/2479860 REPORT
https://bugzilla.redhat.com/2479861 REPORT
https://bugzilla.redhat.com/2479871 REPORT
https://bugzilla.redhat.com/2479873 REPORT
https://bugzilla.redhat.com/2479876 REPORT
https://bugzilla.redhat.com/2479880 REPORT
https://errata.almalinux.org/9/ALSA-2026-21381.html ADVISORY
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "AlmaLinux:9",
        "name": "thunderbird"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "140.11.0-1.el9_8.alma.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "Mozilla Thunderbird is a standalone mail and newsgroup client.  \n\nSecurity Fix(es):  \n\n  * firefox: Incorrect boundary conditions in the JavaScript Engine: JIT component (CVE-2026-8388)\n  * firefox: Other issue in the JavaScript Engine component (CVE-2026-8391)\n  * firefox: Sandbox escape in the Profile Backup component (CVE-2026-8401)\n  * firefox: Integer overflow in the Networking: JAR component (CVE-2026-8956)\n  * firefox: Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151 (CVE-2026-8975)\n  * firefox: Privilege escalation in the DOM: Workers component (CVE-2026-8955)\n  * firefox: Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component (CVE-2026-8968)\n  * firefox: Incorrect boundary conditions, integer overflow in the Audio/Video component (CVE-2026-8954)\n  * firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component (CVE-2026-8958)\n  * firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component (CVE-2026-8946)\n  * firefox: Privilege escalation in the Security component (CVE-2026-8970)\n  * firefox: Same-origin policy bypass in the Networking: HTTP component (CVE-2026-8950)\n  * firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151 (CVE-2026-8974)\n  * firefox: Sandbox escape due to use-after-free in the Disability Access APIs component (CVE-2026-8953)\n  * firefox: Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component (CVE-2026-8959)\n  * firefox: Spoofing issue in the Form Autofill component (CVE-2026-8961)\n  * firefox: Use-after-free in the DOM: Bindings (WebIDL) component (CVE-2026-8947)\n  * firefox: Mitigation bypass in the DOM: Security component (CVE-2026-8962)\n  * firefox: Privilege escalation in the Enterprise Policies component (CVE-2026-8957)\n\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n",
  "id": "ALSA-2026:21381",
  "modified": "2026-05-29T09:48:34Z",
  "published": "2026-05-27T00:00:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:21381"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8388"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8391"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8401"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8946"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8947"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8950"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8953"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8954"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8955"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8956"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8957"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8958"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8959"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8961"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8962"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8968"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8970"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8974"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-8975"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2476469"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2476475"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2476492"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479839"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479840"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479842"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479846"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479847"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479848"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479849"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479852"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479853"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479855"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479860"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479861"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479871"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479873"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479876"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2479880"
    },
    {
      "type": "ADVISORY",
      "url": "https://errata.almalinux.org/9/ALSA-2026-21381.html"
    }
  ],
  "related": [
    "CVE-2026-8388",
    "CVE-2026-8391",
    "CVE-2026-8401",
    "CVE-2026-8946",
    "CVE-2026-8947",
    "CVE-2026-8950",
    "CVE-2026-8953",
    "CVE-2026-8954",
    "CVE-2026-8955",
    "CVE-2026-8956",
    "CVE-2026-8957",
    "CVE-2026-8958",
    "CVE-2026-8959",
    "CVE-2026-8961",
    "CVE-2026-8962",
    "CVE-2026-8968",
    "CVE-2026-8970",
    "CVE-2026-8974",
    "CVE-2026-8975"
  ],
  "schema_version": "1.7.0",
  "summary": "Important: thunderbird security update",
  "upstream": [
    "CVE-2026-8388",
    "CVE-2026-8391",
    "CVE-2026-8401",
    "CVE-2026-8946",
    "CVE-2026-8947",
    "CVE-2026-8950",
    "CVE-2026-8953",
    "CVE-2026-8954",
    "CVE-2026-8955",
    "CVE-2026-8956",
    "CVE-2026-8957",
    "CVE-2026-8958",
    "CVE-2026-8959",
    "CVE-2026-8961",
    "CVE-2026-8962",
    "CVE-2026-8968",
    "CVE-2026-8970",
    "CVE-2026-8974",
    "CVE-2026-8975"
  ]
}



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