CVE catalog

CVE-2026-8971

Same-origin policy bypass in the Networking: JAR…

[CVE catalog]

A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue: Same-origin policy bypass in the Networking: JAR component firefox: thunderbird: Same-origin policy bypass in the Networking: JAR component Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory. The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Severity
Medium · CVSS 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Published
Source
[NVD] · [CVE record]
EPSS
0.21% · Oct 27, 2026

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Version impact has not been established. The original provider fields are retained below.

Provider details and historical evidence
Original provider fields
{
  "package_releases": [],
  "fixed_versions": [],
  "distribution_packages": [
    {
      "name": "firefox",
      "ecosystem": "cpe",
      "fixed_version": "151.0.0"
    },
    {
      "name": "thunderbird",
      "ecosystem": "cpe",
      "fixed_version": "151.0.0"
    },
    {
      "name": "mozjs52",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "18.04",
      "versions": [
        "52.3.1-0ubuntu3",
        "52.3.1-7fakesync1",
        "52.8.1-0ubuntu0.18.04.1",
        "52.9.1-0ubuntu0.18.04.1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs38",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "18.04",
      "versions": [
        "38.8.0~repack1-0ubuntu1",
        "38.8.0~repack1-0ubuntu3",
        "38.8.0~repack1-0ubuntu4"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs68",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "20.04",
      "versions": [
        "68.5.0-1~fakesync",
        "68.5.0-2~fakesync",
        "68.6.0-1",
        "68.6.0-1ubuntu1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs52",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "20.04",
      "versions": [
        "52.9.1-1build1",
        "52.9.1-1ubuntu3"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs102",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "22.04",
      "versions": [
        "102.11.0-0ubuntu0.22.04.1",
        "102.12.0-0ubuntu0.22.04.1",
        "102.13.0-0ubuntu0.22.04.1",
        "102.15.1-0ubuntu0.22.04.1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs78",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "22.04",
      "versions": [
        "78.13.0-1",
        "78.15.0-2",
        "78.15.0-4ubuntu1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs91",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "22.04",
      "versions": [
        "91.5.1-0ubuntu1",
        "91.6.0-1",
        "91.6.0-2",
        "91.7.0-2",
        "91.10.0-0ubuntu1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "thunderbird",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "22.04",
      "versions": [
        "1:91.1.2+build1-0ubuntu1",
        "1:91.3.0+build2-0ubuntu1",
        "1:91.3.1+build1-0ubuntu1",
        "1:91.3.2+build1-0ubuntu1",
        "1:91.4.0+build1.1-0ubuntu1",
        "1:91.4.0+build2-0ubuntu1",
        "1:91.5.0+build1-0ubuntu1",
        "1:91.5.1+build1-0ubuntu1",
        "1:91.6.1+build1-0ubuntu1",
        "1:91.7.0+build1-0ubuntu1",
        "1:91.7.0+build2-0ubuntu1",
        "1:91.8.0+build2-0ubuntu1",
        "1:91.9.1+build1-0ubuntu0.22.04.1",
        "1:91.11.0+build2-0ubuntu0.22.04.1",
        "1:102.2.2+build1-0ubuntu0.22.04.1",
        "1:102.4.2+build2-0ubuntu0.22.04.1",
        "1:102.7.1+build2-0ubuntu0.22.04.1",
        "1:102.8.0+build2-0ubuntu0.22.04.1",
        "1:102.9.0+build1-0ubuntu0.22.04.1",
        "1:102.10.0+build2-0ubuntu0.22.04.1",
        "1:102.11.0+build1-0ubuntu0.22.04.1",
        "1:102.13.0+build1-0ubuntu0.22.04.1",
        "1:102.15.0+build1-0ubuntu0.22.04.1",
        "1:102.15.1+build1-0ubuntu0.22.04.1",
        "1:115.3.1+build1-0ubuntu0.22.04.2",
        "1:115.4.1+build1-0ubuntu0.22.04.1",
        "1:115.5.0+build1-0ubuntu0.22.04.1",
        "1:115.6.0+build2-0ubuntu0.22.04.1",
        "1:115.8.1+build1-0ubuntu0.22.04.1",
        "1:115.9.0+build1-0ubuntu0.22.04.1",
        "1:115.10.1+build1-0ubuntu0.22.04.1",
        "1:115.11.0+build2-0ubuntu0.22.04.1",
        "1:115.12.0+build3-0ubuntu0.22.04.1",
        "1:115.13.0+build5-0ubuntu0.22.04.1",
        "1:115.15.0+build1-0ubuntu0.22.04.1",
        "1:115.16.0+build2-0ubuntu0.22.04.1",
        "1:115.18.0+build1-0ubuntu0.22.04.1",
        "1:128.12.0+build1-0ubuntu0.22.04.1",
        "1:140.7.1+build1-0ubuntu0.22.04.1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs102",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "24.04",
      "versions": [
        "102.15.1-1",
        "102.15.1-3ubuntu2"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    },
    {
      "name": "mozjs115",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "24.04",
      "versions": [
        "115.3.0-0ubuntu1",
        "115.4.0-2",
        "115.5.0-1",
        "115.6.0-1",
        "115.7.0-4",
        "115.8.0-1",
        "115.9.0-1",
        "115.9.0-1build1",
        "115.10.0-1"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-8971"
    }
  ]
}

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

Observed:

References

[CERT-Bund public advisories] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]