Vulnerability-Lookup

FKIE_CVE-2026-6786

Vulnerability from fkie_nvd - Published: 2026-04-26 19:53 - Updated: 2026-06-30 03:21

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
7.5 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Summary

Memory safety bugs present in Firefox ESR 140.9, Thunderbird ESR 140.9, Firefox 149 and Thunderbird 149. 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 was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

References

URL	Tags
security@mozilla.org	https://bugzilla.mozilla.org/buglist.cgi?bug_id=2010727%2C2019004%2C2019224%2C2019547%2C2020378%2C2022381%2C2022608%2C2022785%2C2023120%2C2023128%2C2023140%2C2023279%2C2023836%2C2023882%2C2023925%2C2023950%2C2023959%2C2023965%2C2024243%2C2024245%2C2024247%2C2024253%2C2024346%2C2024357%2C2024416%2C2024420%2C2024429%2C2024432%2C2024455%2C2024466%2C2024468%2C2024476%2C2024664%2C2024666%2C2024669%2C2024670%2C2024671%2C2024761%2C2024918%2C2025292%2C2025332%2C2025348%2C2025384%2C2025395%2C2025458%2C2025461%2C2025463%2C2025481%2C2025483%2C2025485%2C2025494%2C2025506%2C2025511%2C2025513%2C2025520%2C2026277%2C2026282%2C2026288%2C2026289%2C2026311%2C2026312%2C2026869%2C2027152%2C2027161%2C2027238%2C2027261%2C2027269%2C2027274%2C2027280%2C2027281%2C2027300%2C2027302%2C2027331%2C2027339%2C2027340%2C2027738%2C2027975%2C2028000%2C2028011%2C2028289%2C2028525%2C2028728%2C2028887%2C2028888%2C2028896%2C2029063%2C2029064%2C2029290%2C2029291%2C2029294%2C2029300%2C2029304%2C2029316%2C2029317%2C2029401%2C2029415%2C2029430%2C2029457%2C2029727%2C2029735%2C2029743%2C2029752%2C2029754%2C2029776%2C2029809%2C2030324%2C2030370	Broken Link
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2026-30/	Vendor Advisory
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2026-32/	Vendor Advisory
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2026-33/	Vendor Advisory
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2026-34/	Vendor Advisory
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:10757
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:10766
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:10767
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:12285
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:13537
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:15892
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:17477
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:17687
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:17688
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:17689
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:17690
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19041
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19131
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19201
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19348
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19461
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19462
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19463
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19464
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19465
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19466
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19467
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19468
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19469
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19542
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19655
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/errata/RHSA-2026:19704
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://access.redhat.com/security/cve/CVE-2026-6786
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://bugzilla.redhat.com/show_bug.cgi?id=2460088
0b0ca135-0b70-47e7-9f44-1890c2a1c46c	https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6786.json

Impacted products

Vendor	Product	Version
mozilla	firefox	*
mozilla	firefox	*
mozilla	thunderbird	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.10",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "150",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.10",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "150",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "source": "security@mozilla.org"
    },
    {
      "affectedData": [
        {
          "cpes": [
            "cpe:/o:redhat:rhel_els:7"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux Server (v. 7 ELS)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux_eus:10.0"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream EUS (v. 10.0)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10.1",
            "cpe:/o:redhat:enterprise_linux:10.2"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream (v. 10)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:8::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream (v. 8)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_aus:8.4::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream AUS (v.8.4)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_aus:8.6::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream AUS (v.8.6)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:8.6::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream E4S (v.8.6)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_tus:8.6::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream TUS (v.8.6)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:8.8::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream E4S (v.8.8)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_tus:8.8::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream TUS (v.8.8)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:9.0::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream E4S (v.9.0)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:9.2::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream E4S (v.9.2)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_eus:9.4::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream EUS (v.9.4)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:rhel_eus:9.6::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream EUS (v.9.6)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9::appstream"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux AppStream (v. 9)",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux 6",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "affected",
          "product": "Red Hat Enterprise Linux 7",
          "vendor": "Red Hat"
        }
      ],
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*",
              "matchCriteriaId": "67B01D49-66FA-4C76-9EB4-2B8CD61FBEB2",
              "versionEndExcluding": "150.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*",
              "matchCriteriaId": "528443E0-C15A-4E70-9187-8E1BAAE84A42",
              "versionEndExcluding": "140.10.0",
              "versionStartIncluding": "140.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*",
              "matchCriteriaId": "6A8A3284-C06C-4591-9548-5324BD91C4FC",
              "versionEndExcluding": "140.10.0",
              "versionStartIncluding": "140.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Memory safety bugs present in Firefox ESR 140.9, Thunderbird ESR 140.9, Firefox 149 and Thunderbird 149. 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 was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10."
    }
  ],
  "id": "CVE-2026-6786",
  "lastModified": "2026-06-30T03:21:17.457",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.9,
        "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-6786",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-04-22T03:56:14.200175Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-26T19:53:39.640",
  "references": [
    {
      "source": "security@mozilla.org",
      "tags": [
        "Broken Link"
      ],
      "url": "https://bugzilla.mozilla.org/buglist.cgi?bug_id=2010727%2C2019004%2C2019224%2C2019547%2C2020378%2C2022381%2C2022608%2C2022785%2C2023120%2C2023128%2C2023140%2C2023279%2C2023836%2C2023882%2C2023925%2C2023950%2C2023959%2C2023965%2C2024243%2C2024245%2C2024247%2C2024253%2C2024346%2C2024357%2C2024416%2C2024420%2C2024429%2C2024432%2C2024455%2C2024466%2C2024468%2C2024476%2C2024664%2C2024666%2C2024669%2C2024670%2C2024671%2C2024761%2C2024918%2C2025292%2C2025332%2C2025348%2C2025384%2C2025395%2C2025458%2C2025461%2C2025463%2C2025481%2C2025483%2C2025485%2C2025494%2C2025506%2C2025511%2C2025513%2C2025520%2C2026277%2C2026282%2C2026288%2C2026289%2C2026311%2C2026312%2C2026869%2C2027152%2C2027161%2C2027238%2C2027261%2C2027269%2C2027274%2C2027280%2C2027281%2C2027300%2C2027302%2C2027331%2C2027339%2C2027340%2C2027738%2C2027975%2C2028000%2C2028011%2C2028289%2C2028525%2C2028728%2C2028887%2C2028888%2C2028896%2C2029063%2C2029064%2C2029290%2C2029291%2C2029294%2C2029300%2C2029304%2C2029316%2C2029317%2C2029401%2C2029415%2C2029430%2C2029457%2C2029727%2C2029735%2C2029743%2C2029752%2C2029754%2C2029776%2C2029809%2C2030324%2C2030370"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
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      "url": "https://www.mozilla.org/security/advisories/mfsa2026-30/"
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      "url": "https://www.mozilla.org/security/advisories/mfsa2026-33/"
    },
    {
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      "url": "https://www.mozilla.org/security/advisories/mfsa2026-34/"
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CVE-2026-6786 (GCVE-0-2026-6786)

Vulnerability from cvelistv5 – Published: 2026-04-21 12:41 – Updated: 2026-06-30 12:06

Title

Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150

Summary

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-416 - Use After Free
CWE-125 - Out-of-bounds Read
CWE-787 - Out-of-bounds Write

Assigner

mozilla

References

35 references

URL	Tags
https://bugzilla.mozilla.org/buglist.cgi?bug_id=2…
https://www.mozilla.org/security/advisories/mfsa2…
https://www.mozilla.org/security/advisories/mfsa2…
https://www.mozilla.org/security/advisories/mfsa2…
https://www.mozilla.org/security/advisories/mfsa2…
https://access.redhat.com/security/cve/CVE-2026-6786	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2460088	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex
https://access.redhat.com/errata/RHSA-2026:19704	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17690	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19463	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:10767	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:12285	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19041	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19131	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:10766	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:13537	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19655	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19465	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19542	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19466	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17477	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19467	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17687	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19468	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17689	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19461	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19464	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19469	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17688	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19462	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:10757	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:15892	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19201	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19348	vendor-advisoryx_refsource_REDHAT

Impacted products

21 products

Vendor	Product	Version
Mozilla	Firefox	Unaffected: 140.10 , ≤ 140.* (rpm) Unaffected: 150 , ≤ * (rpm)
Mozilla	Thunderbird	Unaffected: 140.10 , ≤ 140.* (rpm) Unaffected: 150 , ≤ * (rpm)
Red Hat	Red Hat Enterprise Linux Server (v. 7 ELS)	cpe:/o:redhat:rhel_els:7
Red Hat	Red Hat Enterprise Linux AppStream EUS (v. 10.0)	cpe:/o:redhat:enterprise_linux_eus:10.0
Red Hat	Red Hat Enterprise Linux AppStream (v. 10)	cpe:/o:redhat:enterprise_linux:10.1 cpe:/o:redhat:enterprise_linux:10.2
Red Hat	Red Hat Enterprise Linux AppStream (v. 8)	cpe:/a:redhat:enterprise_linux:8::appstream
Red Hat	Red Hat Enterprise Linux AppStream AUS (v.8.4)	cpe:/a:redhat:rhel_aus:8.4::appstream
Red Hat	Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)	cpe:/a:redhat:rhel_eus_long_life:8.4::appstream
Red Hat	Red Hat Enterprise Linux AppStream AUS (v.8.6)	cpe:/a:redhat:rhel_aus:8.6::appstream
Red Hat	Red Hat Enterprise Linux AppStream E4S (v.8.6)	cpe:/a:redhat:rhel_e4s:8.6::appstream
Red Hat	Red Hat Enterprise Linux AppStream TUS (v.8.6)	cpe:/a:redhat:rhel_tus:8.6::appstream
Red Hat	Red Hat Enterprise Linux AppStream E4S (v.8.8)	cpe:/a:redhat:rhel_e4s:8.8::appstream
Red Hat	Red Hat Enterprise Linux AppStream TUS (v.8.8)	cpe:/a:redhat:rhel_tus:8.8::appstream
Red Hat	Red Hat Enterprise Linux AppStream E4S (v.9.0)	cpe:/a:redhat:rhel_e4s:9.0::appstream
Red Hat	Red Hat Enterprise Linux AppStream E4S (v.9.2)	cpe:/a:redhat:rhel_e4s:9.2::appstream
Red Hat	Red Hat Enterprise Linux AppStream EUS (v.9.4)	cpe:/a:redhat:rhel_eus:9.4::appstream
Red Hat	Red Hat Enterprise Linux AppStream EUS (v.9.6)	cpe:/a:redhat:rhel_eus:9.6::appstream
Red Hat	Red Hat Enterprise Linux AppStream (v. 9)	cpe:/a:redhat:enterprise_linux:9::appstream
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7

Credits

Alex Franchuk, Andrew McCreight, Brian Grinstead, Christian Holler, Jan de Mooij, Maurice Dauer, Sebastian Hengst, Tom Schuster and the Mozilla Fuzzing Team

Show details on NVD website

JSON

To clipboard

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            "url": "https://access.redhat.com/errata/RHSA-2026:19469"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2026:17688"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2026:19462"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2026:10757"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2026:15892"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2026:19201"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_refsource_REDHAT"
            ],
            "url": "https://access.redhat.com/errata/RHSA-2026:19348"
          }
        ],
        "solutions": [
          {
            "lang": "en",
            "value": "RHSA-2026:19704: Red Hat Enterprise Linux Server (v. 7 ELS)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:17690: Red Hat Enterprise Linux AppStream EUS (v. 10.0)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19463: Red Hat Enterprise Linux AppStream EUS (v. 10.0)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:10767: Red Hat Enterprise Linux AppStream (v. 10)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:12285: Red Hat Enterprise Linux AppStream (v. 10)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19041: Red Hat Enterprise Linux AppStream (v. 10)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19131: Red Hat Enterprise Linux AppStream (v. 10)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:10766: Red Hat Enterprise Linux AppStream (v. 8)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:13537: Red Hat Enterprise Linux AppStream (v. 8)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19655: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19465: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19542: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream E4S (v.8.6), Red Hat Enterprise Linux AppStream TUS (v.8.6)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19466: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream E4S (v.8.6), Red Hat Enterprise Linux AppStream TUS (v.8.6)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:17477: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19467: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:17687: Red Hat Enterprise Linux AppStream E4S (v.9.0)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19468: Red Hat Enterprise Linux AppStream E4S (v.9.0)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:17689: Red Hat Enterprise Linux AppStream E4S (v.9.2)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19461: Red Hat Enterprise Linux AppStream E4S (v.9.2)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19464: Red Hat Enterprise Linux AppStream EUS (v.9.4)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19469: Red Hat Enterprise Linux AppStream EUS (v.9.4)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:17688: Red Hat Enterprise Linux AppStream EUS (v.9.6)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19462: Red Hat Enterprise Linux AppStream EUS (v.9.6)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:10757: Red Hat Enterprise Linux AppStream (v. 9)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:15892: Red Hat Enterprise Linux AppStream (v. 9)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19201: Red Hat Enterprise Linux AppStream (v. 9)"
          },
          {
            "lang": "en",
            "value": "RHSA-2026:19348: Red Hat Enterprise Linux AppStream (v. 9)"
          }
        ],
        "timeline": [
          {
            "lang": "en",
            "time": "2026-04-21T14:01:48.769Z",
            "value": "Reported to Red Hat."
          },
          {
            "lang": "en",
            "time": "2026-04-21T12:41:14.629Z",
            "value": "Made public."
          }
        ],
        "title": "firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150",
        "x_adpType": "supplier",
        "x_generator": {
          "engine": "sadp-cli 1.0.0"
        }
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.10",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "150",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.10",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "150",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Alex Franchuk, Andrew McCreight, Brian Grinstead, Christian Holler, Jan de Mooij, Maurice Dauer, Sebastian Hengst, Tom Schuster and the Mozilla Fuzzing Team"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Memory safety bugs present in Firefox ESR 140.9, Thunderbird ESR 140.9, Firefox 149 and Thunderbird 149. 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 was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10."
            }
          ],
          "value": "Memory safety bugs present in Firefox ESR 140.9, Thunderbird ESR 140.9, Firefox 149 and Thunderbird 149. 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 was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-21T23:35:23.487Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "name": "Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150",
          "url": "https://bugzilla.mozilla.org/buglist.cgi?bug_id=2010727%2C2019004%2C2019224%2C2019547%2C2020378%2C2022381%2C2022608%2C2022785%2C2023120%2C2023128%2C2023140%2C2023279%2C2023836%2C2023882%2C2023925%2C2023950%2C2023959%2C2023965%2C2024243%2C2024245%2C2024247%2C2024253%2C2024346%2C2024357%2C2024416%2C2024420%2C2024429%2C2024432%2C2024455%2C2024466%2C2024468%2C2024476%2C2024664%2C2024666%2C2024669%2C2024670%2C2024671%2C2024761%2C2024918%2C2025292%2C2025332%2C2025348%2C2025384%2C2025395%2C2025458%2C2025461%2C2025463%2C2025481%2C2025483%2C2025485%2C2025494%2C2025506%2C2025511%2C2025513%2C2025520%2C2026277%2C2026282%2C2026288%2C2026289%2C2026311%2C2026312%2C2026869%2C2027152%2C2027161%2C2027238%2C2027261%2C2027269%2C2027274%2C2027280%2C2027281%2C2027300%2C2027302%2C2027331%2C2027339%2C2027340%2C2027738%2C2027975%2C2028000%2C2028011%2C2028289%2C2028525%2C2028728%2C2028887%2C2028888%2C2028896%2C2029063%2C2029064%2C2029290%2C2029291%2C2029294%2C2029300%2C2029304%2C2029316%2C2029317%2C2029401%2C2029415%2C2029430%2C2029457%2C2029727%2C2029735%2C2029743%2C2029752%2C2029754%2C2029776%2C2029809%2C2030324%2C2030370"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-30/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-32/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-33/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-34/"
        }
      ],
      "title": "Memory safety bugs fixed in Firefox ESR 140.10, Thunderbird ESR 140.10, Firefox 150 and Thunderbird 150"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2026-6786",
    "datePublished": "2026-04-21T12:41:14.629Z",
    "dateReserved": "2026-04-21T12:41:14.326Z",
    "dateUpdated": "2026-06-30T12:06:02.983Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Action not permitted

FKIE_CVE-2026-6786

CVE-2026-6786 (GCVE-0-2026-6786)

Tags

Sightings

Nomenclature