CVE-2026-74959 (GCVE-0-2026-74959)

Vulnerability from cvelistv5 – Published: 2026-08-18 12:23 – Updated: 2026-08-18 18:55
VLAI
Title
Mitigation bypass in the Storage: Cache API component
Summary
Mitigation bypass in the Storage: Cache API component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version CPE status
Mozilla Firefox Unaffected: 140.14 , ≤ 140.* (rpm)
Unaffected: 153.1 , ≤ 153.* (rpm)
Unaffected: 154 , ≤ * (rpm)
guessed Create a notification for this product.
Mozilla Thunderbird Unaffected: 140.14 , ≤ 140.* (rpm)
Unaffected: 153.1 , ≤ 153.* (rpm)
Unaffected: 154 , ≤ * (rpm)
guessed Create a notification for this product.
Credits
David Bors at Snyk Security Labs
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.14",
              "versionType": "rpm"
            },
            {
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              "status": "unaffected",
              "version": "153.1",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "154",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
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              "status": "unaffected",
              "version": "140.14",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.1",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "154",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "David Bors at Snyk Security Labs"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Mitigation bypass in the Storage: Cache API component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1."
            }
          ],
          "value": "Mitigation bypass in the Storage: Cache API component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-18T18:55:10.521Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2047853"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-74/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-76/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-77/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-78/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-79/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-80/"
        }
      ],
      "title": "Mitigation bypass in the Storage: Cache API component"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2026-74959",
    "datePublished": "2026-08-18T12:23:31.322Z",
    "dateReserved": "2026-08-17T11:58:20.360Z",
    "dateUpdated": "2026-08-18T18:55:10.521Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
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      "date": "2026-08-20",
      "epss": "0.00164",
      "percentile": "0.06091"
    },
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    "redhat_vex": {
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      "current_release_date": "2026-08-19T10:01:26+00:00",
      "cve": "CVE-2026-74959",
      "id": "CVE-2026-74959",
      "initial_release_date": "2026-08-18T12:23:31.322000+00:00",
      "product_status:known_affected": "23",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "firefox: thunderbird: Mitigation bypass in the Storage: Cache API component",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74959.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-08-21T00:38:42Z",
      "cve": "CVE-2026-74959",
      "id": "CVE-2026-74959",
      "initial_release_date": "2026-08-21T00:38:42Z",
      "product_status:first_fixed": "8",
      "product_status:known_affected": "64",
      "product_status:recommended": "77",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-74959",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-74959.json",
      "version": "2"
    }
  }
}



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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.

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