CVE-2026-8391 (GCVE-0-2026-8391)

Vulnerability from cvelistv5 – Published: 2026-05-12 12:36 – Updated: 2026-05-19 17:10
VLAI?
Title
Other issue in the JavaScript Engine component
Summary
Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-20 - Improper Input Validation
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 115.36 , ≤ 115.* (rpm)
Unaffected: 140.11 , ≤ 140.* (rpm)
Unaffected: 150.0.3 , ≤ * (rpm)
Create a notification for this product.
Mozilla Thunderbird Unaffected: 140.11 , ≤ * (rpm)
Create a notification for this product.
Credits
ggwhyp
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 5.3,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "LOW",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-8391",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-13T15:47:19.047188Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-20",
                "description": "CWE-20 Improper Input Validation",
                "lang": "en",
                "type": "CWE"
              }
            ]
          },
          {
            "descriptions": [
              {
                "cweId": "CWE-79",
                "description": "CWE-79 Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
                "lang": "en",
                "type": "CWE"
              }
            ]
          },
          {
            "descriptions": [
              {
                "cweId": "CWE-119",
                "description": "CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-13T15:47:30.418Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "115.*",
              "status": "unaffected",
              "version": "115.36",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.11",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "150.0.3",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "140.11",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "ggwhyp"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11."
            }
          ],
          "value": "Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-19T17:10:47.079Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2038575"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-45/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-47/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-48/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-51/"
        }
      ],
      "title": "Other issue in the JavaScript Engine component"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2026-8391",
    "datePublished": "2026-05-12T12:36:15.548Z",
    "dateReserved": "2026-05-12T12:36:14.816Z",
    "dateUpdated": "2026-05-19T17:10:47.079Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-8391",
      "date": "2026-05-22",
      "epss": "0.00109",
      "percentile": "0.28761"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-8391\",\"sourceIdentifier\":\"security@mozilla.org\",\"published\":\"2026-05-12T14:17:12.173\",\"lastModified\":\"2026-05-19T18:16:31.347\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N\",\"baseScore\":5.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":1.4}]},\"weaknesses\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-20\"},{\"lang\":\"en\",\"value\":\"CWE-79\"},{\"lang\":\"en\",\"value\":\"CWE-119\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*\",\"versionEndExcluding\":\"150.0.3\",\"matchCriteriaId\":\"B13F359A-1C15-48B4-8319-AD42CC852E8C\"}]}]}],\"references\":[{\"url\":\"https://bugzilla.mozilla.org/show_bug.cgi?id=2038575\",\"source\":\"security@mozilla.org\",\"tags\":[\"Permissions Required\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-45/\",\"source\":\"security@mozilla.org\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-47/\",\"source\":\"security@mozilla.org\"},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-48/\",\"source\":\"security@mozilla.org\"},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-51/\",\"source\":\"security@mozilla.org\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"LOW\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-8391\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-05-13T15:47:19.047188Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-20\", \"description\": \"CWE-20 Improper Input Validation\"}]}, {\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-79\", \"description\": \"CWE-79 Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)\"}]}, {\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-119\", \"description\": \"CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-05-13T15:47:13.828Z\"}}], \"cna\": {\"title\": \"Other issue in the JavaScript Engine component\", \"credits\": [{\"lang\": \"en\", \"value\": \"ggwhyp\"}], \"affected\": [{\"vendor\": \"Mozilla\", \"product\": \"Firefox\", \"versions\": [{\"status\": \"unaffected\", \"version\": \"115.36\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"115.*\"}, {\"status\": \"unaffected\", \"version\": \"140.11\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"140.*\"}, {\"status\": \"unaffected\", \"version\": \"150.0.3\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"*\"}]}, {\"vendor\": \"Mozilla\", \"product\": \"Thunderbird\", \"versions\": [{\"status\": \"unaffected\", \"version\": \"140.11\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"*\"}]}], \"references\": [{\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=2038575\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-45/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-47/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-48/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-51/\"}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.\", \"base64\": false}]}], \"providerMetadata\": {\"orgId\": \"f16b083a-5664-49f3-a51e-8d479e5ed7fe\", \"shortName\": \"mozilla\", \"dateUpdated\": \"2026-05-19T17:10:47.079Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-8391\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-05-19T17:10:47.079Z\", \"dateReserved\": \"2026-05-12T12:36:14.816Z\", \"assignerOrgId\": \"f16b083a-5664-49f3-a51e-8d479e5ed7fe\", \"datePublished\": \"2026-05-12T12:36:15.548Z\", \"assignerShortName\": \"mozilla\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




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.