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rlsa-2026:58897
Vulnerability from osv_rocky
Published
2026-08-25 12:04
Modified
2026-09-05 18:12
Summary
Important: firefox security update
Details

Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.

Security Fix(es):

  • firefox: thunderbird: Mitigation bypass in the Data Loss Prevention component (CVE-2026-74983)

  • firefox: thunderbird: Site isolation issue in the Graphics: CanvasWebGL component (CVE-2026-74934)

  • firefox: thunderbird: Privilege escalation in the Networking: Cookies component (CVE-2026-74953)

  • firefox: thunderbird: Internally found bugs fixed in Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154 (CVE-2026-74987)

  • firefox: thunderbird: Information disclosure in the Graphics component (CVE-2026-74948)

  • firefox: thunderbird: Use-after-free in the Graphics: ImageLib component (CVE-2026-74943)

  • firefox: thunderbird: Information disclosure in the DOM: UI Events & Focus Handling component (CVE-2026-74971)

  • firefox: thunderbird: Privilege escalation in the Graphics: CanvasWebGL component (CVE-2026-74941)

  • firefox: Privilege escalation in the Shell Integration component (CVE-2026-74965)

  • firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-74946)

  • firefox: Race condition, use-after-free in the Graphics component (CVE-2026-74973)

  • firefox: thunderbird: Privilege escalation due to use-after-free in the Graphics: Canvas2D component (CVE-2026-74949)

  • firefox: thunderbird: Internally found bugs fixed in Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154 (CVE-2026-74990)

  • firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component (CVE-2026-74936)

  • firefox: thunderbird: Use-after-free in the Graphics: Text component (CVE-2026-74940)

  • firefox: thunderbird: Site isolation issue in the WebExtensions component (CVE-2026-74960)

  • firefox: thunderbird: Use-after-free in the Layout: Text and Fonts component (CVE-2026-74969)

  • firefox: thunderbird: Mitigation bypass in the Storage: Cache API component (CVE-2026-74959)

  • firefox: thunderbird: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2026-74976)

  • firefox: thunderbird: Same-origin policy bypass in the Graphics: ImageLib component (CVE-2026-74974)

  • firefox: thunderbird: Mitigation bypass in the Safe Browsing component (CVE-2026-74957)

  • firefox: thunderbird: Same-origin policy bypass in the Audio/Video: Playback component (CVE-2026-74967)

  • firefox: Privilege escalation in the Remote Settings Client component (CVE-2026-74942)

  • firefox: thunderbird: Privilege escalation in the DOM: Navigation component (CVE-2026-74939)

  • firefox: thunderbird: Information disclosure in the DOM: Push Subscriptions component (CVE-2026-74972)

  • firefox: thunderbird: Information disclosure in the Graphics: Text component (CVE-2026-74945)

  • firefox: thunderbird: Same-origin policy bypass in the Networking: Cookies component (CVE-2026-74963)

  • firefox: thunderbird: Use-after-free in the DOM: Core & HTML component (CVE-2026-74944)

  • firefox: Integer overflow in the Graphics component (CVE-2026-74964)

  • firefox: Site isolation issue in the Networking: Cookies component (CVE-2026-74962)

  • firefox: thunderbird: Privilege escalation in the DOM: Networking component (CVE-2026-74935)

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.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Credits
Rocky Enterprise Software Foundation
Red Hat
References
https://errata.rockylinux.org/RLSA-2026:58897 ADVISORY
https://bugzilla.redhat.com/show_bug.cgi?id=2517819 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517820 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517822 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517823 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517825 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517826 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517831 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517833 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517834 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517835 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517836 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517837 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517839 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517840 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517841 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517845 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517846 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517849 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517851 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517853 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517856 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517858 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517859 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517860 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517862 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517863 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517866 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517868 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517870 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517872 REPORT
https://bugzilla.redhat.com/show_bug.cgi?id=2517874 REPORT
https://access.redhat.com/errata/RHSA-2026:58897 ADVISORY
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:9",
        "name": "firefox",
        "purl": "pkg:rpm/rocky-linux/firefox?distro=rocky-linux-9\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:140.14.0-1.el9_8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "database_specific": {
    "license": "CC-BY-4.0",
    "license_url": "https://creativecommons.org/licenses/by/4.0/",
    "source_advisory": "RHSA-2026:58897"
  },
  "details": "Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.\n\nSecurity Fix(es):\n\n* firefox: thunderbird: Mitigation bypass in the Data Loss Prevention component (CVE-2026-74983)\n\n* firefox: thunderbird: Site isolation issue in the Graphics: CanvasWebGL component (CVE-2026-74934)\n\n* firefox: thunderbird: Privilege escalation in the Networking: Cookies component (CVE-2026-74953)\n\n* firefox: thunderbird: Internally found bugs fixed in Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154 (CVE-2026-74987)\n\n* firefox: thunderbird: Information disclosure in the Graphics component (CVE-2026-74948)\n\n* firefox: thunderbird: Use-after-free in the Graphics: ImageLib component (CVE-2026-74943)\n\n* firefox: thunderbird: Information disclosure in the DOM: UI Events \u0026 Focus Handling component (CVE-2026-74971)\n\n* firefox: thunderbird: Privilege escalation in the Graphics: CanvasWebGL component (CVE-2026-74941)\n\n* firefox: Privilege escalation in the Shell Integration component (CVE-2026-74965)\n\n* firefox: thunderbird: Privilege escalation due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2026-74946)\n\n* firefox: Race condition, use-after-free in the Graphics component (CVE-2026-74973)\n\n* firefox: thunderbird: Privilege escalation due to use-after-free in the Graphics: Canvas2D component (CVE-2026-74949)\n\n* firefox: thunderbird: Internally found bugs fixed in Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154 (CVE-2026-74990)\n\n* firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component (CVE-2026-74936)\n\n* firefox: thunderbird: Use-after-free in the Graphics: Text component (CVE-2026-74940)\n\n* firefox: thunderbird: Site isolation issue in the WebExtensions component (CVE-2026-74960)\n\n* firefox: thunderbird: Use-after-free in the Layout: Text and Fonts component (CVE-2026-74969)\n\n* firefox: thunderbird: Mitigation bypass in the Storage: Cache API component (CVE-2026-74959)\n\n* firefox: thunderbird: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2026-74976)\n\n* firefox: thunderbird: Same-origin policy bypass in the Graphics: ImageLib component (CVE-2026-74974)\n\n* firefox: thunderbird: Mitigation bypass in the Safe Browsing component (CVE-2026-74957)\n\n* firefox: thunderbird: Same-origin policy bypass in the Audio/Video: Playback component (CVE-2026-74967)\n\n* firefox: Privilege escalation in the Remote Settings Client component (CVE-2026-74942)\n\n* firefox: thunderbird: Privilege escalation in the DOM: Navigation component (CVE-2026-74939)\n\n* firefox: thunderbird: Information disclosure in the DOM: Push Subscriptions component (CVE-2026-74972)\n\n* firefox: thunderbird: Information disclosure in the Graphics: Text component (CVE-2026-74945)\n\n* firefox: thunderbird: Same-origin policy bypass in the Networking: Cookies component (CVE-2026-74963)\n\n* firefox: thunderbird: Use-after-free in the DOM: Core \u0026 HTML component (CVE-2026-74944)\n\n* firefox: Integer overflow in the Graphics component (CVE-2026-74964)\n\n* firefox: Site isolation issue in the Networking: Cookies component (CVE-2026-74962)\n\n* firefox: thunderbird: Privilege escalation in the DOM: Networking component (CVE-2026-74935)\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.",
  "id": "RLSA-2026:58897",
  "modified": "2026-09-05T18:12:55.639741Z",
  "published": "2026-08-25T12:04:25.606210Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:58897"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517819"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517820"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517822"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517823"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517825"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517826"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517831"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517833"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517834"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517835"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517836"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517837"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517839"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517840"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517841"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517845"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517846"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517849"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517851"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517853"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517856"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517858"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517859"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517860"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517862"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517863"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517866"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517868"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517870"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517872"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517874"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:58897"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Important: firefox security update",
  "upstream": [
    "CVE-2026-74934",
    "CVE-2026-74935",
    "CVE-2026-74936",
    "CVE-2026-74939",
    "CVE-2026-74940",
    "CVE-2026-74941",
    "CVE-2026-74942",
    "CVE-2026-74943",
    "CVE-2026-74944",
    "CVE-2026-74945",
    "CVE-2026-74946",
    "CVE-2026-74948",
    "CVE-2026-74949",
    "CVE-2026-74953",
    "CVE-2026-74957",
    "CVE-2026-74959",
    "CVE-2026-74960",
    "CVE-2026-74962",
    "CVE-2026-74963",
    "CVE-2026-74964",
    "CVE-2026-74965",
    "CVE-2026-74967",
    "CVE-2026-74969",
    "CVE-2026-74971",
    "CVE-2026-74972",
    "CVE-2026-74973",
    "CVE-2026-74974",
    "CVE-2026-74976",
    "CVE-2026-74983",
    "CVE-2026-74987",
    "CVE-2026-74990"
  ]
}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.