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OESA-2026-1877 (CVE-2026-5731)

Vulnerability from osv_openeuler – Published: 2026-04-11 11:10 – Updated: 2026-08-06 11:10 – Source website
VLAI
Summary
firefox security update
Details

Mozilla Firefox is an open-source web browser, designed for standards compliance, performance and portability. %if 0 %global moz_debug_prefix /lib/debug %global moz_debug_dir /lib/debug/ %global uname_m %(uname -m) %global symbols_file_name -.en-US.-%(uname.crashreporter-symbols.zip %global symbols_file_path /lib/debug//-.en-US.-%(uname.crashreporter-symbols.zip %global _find_debuginfo_opts -p /lib/debug//-.en-US.-%(uname.crashreporter-symbols.zip -o debugcrashreporter.list %global crashreporter_pkg_name mozilla-crashreporter--debuginfo

Security Fix(es):

Memory safety bugs present in Firefox ESR 115.34.0, Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 149.0.2, Firefox ESR < 115.34.1, and Firefox ESR < 140.9.1.(CVE-2026-5731)

Incorrect boundary conditions, integer overflow in the Graphics: Text component. This vulnerability affects Firefox < 149.0.2 and Firefox ESR < 140.9.1.(CVE-2026-5732)

Memory safety bugs present in Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 149.0.2 and Firefox ESR < 140.9.1.(CVE-2026-5734)

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "firefox-140.9.1-1.oe2403sp3.aarch64.rpm",
          "firefox-debuginfo-140.9.1-1.oe2403sp3.aarch64.rpm",
          "firefox-debugsource-140.9.1-1.oe2403sp3.aarch64.rpm"
        ],
        "src": [
          "firefox-140.9.1-1.oe2403sp3.src.rpm"
        ],
        "x86_64": [
          "firefox-140.9.1-1.oe2403sp3.x86_64.rpm",
          "firefox-debuginfo-140.9.1-1.oe2403sp3.x86_64.rpm",
          "firefox-debugsource-140.9.1-1.oe2403sp3.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP3",
        "name": "firefox",
        "purl": "pkg:rpm/openEuler/firefox\u0026distro=openEuler-24.03-LTS-SP3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "140.9.1-1.oe2403sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Critical"
  },
  "details": "Mozilla Firefox is an open-source web browser, designed for standards compliance, performance and portability. %if 0 %global moz_debug_prefix /lib/debug %global moz_debug_dir /lib/debug/ %global uname_m %(uname -m) %global symbols_file_name -.en-US.-%(uname.crashreporter-symbols.zip %global symbols_file_path /lib/debug//-.en-US.-%(uname.crashreporter-symbols.zip %global _find_debuginfo_opts -p /lib/debug//-.en-US.-%(uname.crashreporter-symbols.zip -o debugcrashreporter.list %global crashreporter_pkg_name mozilla-crashreporter--debuginfo\r\n\r\nSecurity Fix(es):\n\nMemory safety bugs present in Firefox ESR 115.34.0, Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox \u0026lt; 149.0.2, Firefox ESR \u0026lt; 115.34.1, and Firefox ESR \u0026lt; 140.9.1.(CVE-2026-5731)\n\nIncorrect boundary conditions, integer overflow in the Graphics: Text component. This vulnerability affects Firefox \u0026lt; 149.0.2 and Firefox ESR \u0026lt; 140.9.1.(CVE-2026-5732)\n\nMemory safety bugs present in Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox \u0026lt; 149.0.2 and Firefox ESR \u0026lt; 140.9.1.(CVE-2026-5734)",
  "id": "OESA-2026-1877",
  "modified": "2026-08-06T11:10:53Z",
  "published": "2026-04-11T11:10:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1877"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5731"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5732"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5734"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "firefox security update",
  "upstream": [
    "CVE-2026-5731",
    "CVE-2026-5732",
    "CVE-2026-5734"
  ]
}



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