CriticalCVE-2026-74987

    firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer (CVE-2026-74987)

    Published Last modified Sources: BSI

    What is affected, what to do

    Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

    Update Mozilla Firefox to version 140.14.0, Mozilla Firefox to version 153.1.0, Mozilla Thunderbird to version 140.14.0.

    Affected
    • Mozilla Firefox lt *..140.14.0
    • Mozilla Firefox lt 141.0..153.1.0
    • Mozilla Thunderbird lt *..140.14.0
    • Mozilla Thunderbird lt 141.0..153.1.0
    Fixed in
    • Mozilla Firefox 140.14.0
    • Mozilla Firefox 153.1.0
    • Mozilla Thunderbird 140.14.0
    • Mozilla Thunderbird 153.1.0

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    9.8

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: Vendor (CNA), CVSS v3

    9.8

    CVSS v3

    Severity Critical on the scale from 0 to 10.

    Source: BSI

    0.7 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 53.8

    Show all metrics
    Severity
    Critical
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    85.85 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    no public PoC known
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    9.8 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    9.8
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    0.7 %
    Low — model estimates < 1% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    53.8
    High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published
    CISA assessment (SSVC)
    Exploitation: none known · automatable · Technical impact: total
    Source: CISA Vulnrichment, as of 19 August 2026
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-119

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

    Source: BSI WID Portal

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    mozillafirefox
    • 116.0 – < 140.14.0
    • 141.0 – < 153.1.0
    • 141.0 – < 154.0.0
    • 141.0.0 – < 153.1.0
    • 153.0
    • < 115.39.0
    • < 140.14.0
    • < 153.1.0
    • < 154.0.0
    • 140.14.0
    • 153.1.0
    • 154.0.0
    • 153.1.0
    • —
    • 115.39.0
    • 140.14.0
    • 153.1.0
    • 154.0.0
    mozillafirefox_mobile
    • < 154.0
    • 154.0
    mozillathunderbird
    • 141.0 – < 153.1.0
    • 153.0 – < 153.1.0
    • < 140.14.0
    • < 153.1.0
    • < 154.0
    • 153.1.0
    • 153.1.0
    • 140.14.0
    • 153.1.0
    • 154.0
    MozillaFirefox
    • < 154
    • 154
    MozillaFirefox ESR
    • < 115.39
    • < 140.14
    • < 153.1
    • 115.39
    • 140.14
    • 153.1
    MozillaThunderbird
    • < 140.14
    • < 153.1
    • < 154
    • 140.14
    • 153.1
    • 154
    From bundled advisories, not CVE-specific (7)

    Product list of a bundled advisory that does not state which product this CVE affects.

    Products from bundled advisories
    Affected versionsFixed in
    MozillaFirefox
    • < 155
    • 155
    MozillaFirefox ESR
    • < 115.40
    • < 140.15
    • < 153.2
    • 115.40
    • 140.15
    • 153.2
    MozillaThunderbird
    • < 140.15
    • < 153.2
    • < 155
    • 140.15
    • 153.2
    • 155

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxdebianfirefox-esrbookworm
    Linuxdebianfirefox-esrbullseye
    Linuxdebianfirefox-esrtrixie
    Linuxdebianthunderbirdbookworm
    Linuxdebianthunderbirdbullseye
    Linuxdebianthunderbirdtrixie

    Weakness classes (CWE)

    • CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer

      Class

      The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

      Entry at MITRE CWE-119

    References & sources

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. Record modifiedMozilla

      Description added or changed

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionchanged
      Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
      Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

      Source identifier: security@mozilla.org

    2. Record modifiedMozilla

      Description added or changed

      Show 28 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionchanged
      Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
      Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
      Referenceadded
      —
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=1500946%2C1788109%2C2045379%2C2045380%2C2049339%2C2049393%2C2053580%2C2054662%2C2054665%2C2054673%2C2054785%2C2058645
      Referenceadded
      —
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048797%2C2050536%2C2053272%2C2053579%2C2057115%2C2057116%2C2057130%2C2057991%2C2057995%2C2058002%2C2058008%2C2058032%2C2058102%2C2058667
      Referenceadded
      —
      https://bugzilla.mozilla.org/show_bug.cgi?id=2059424
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-74/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-76/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-77/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-78/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-79/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-80/
      Referenceremoved
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=1500946%2C1788109%2C2045379%2C2045380%2C2049339%2C2049393%2C2053580%2C2054662%2C2054665%2C2054673%2C2054785%2C2058645
      —
      Referenceremoved
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048797%2C2050536%2C2053272%2C2053579%2C2057115%2C2057116%2C2057130%2C2057991%2C2057995%2C2058002%2C2058008%2C2058032%2C2058102%2C2058667
      —
      Referenceremoved
      https://bugzilla.mozilla.org/show_bug.cgi?id=2059424
      —
      Referenceremoved
      https://www.mozilla.org/security/advisories/mfsa2026-74/
      —
      Referenceremoved
      https://www.mozilla.org/security/advisories/mfsa2026-76/
      —
      Referenceremoved
      https://www.mozilla.org/security/advisories/mfsa2026-77/
      —
      Referenceremoved
      https://www.mozilla.org/security/advisories/mfsa2026-78/
      —
      Referenceremoved
      https://www.mozilla.org/security/advisories/mfsa2026-79/
      —
      Referenceremoved
      https://www.mozilla.org/security/advisories/mfsa2026-80/
      —
      Reference typeremoved
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=1500946%2C1788109%2C2045379%2C2045380%2C2049339%2C2049393%2C2053580%2C2054662%2C2054665%2C2054673%2C2054785%2C2058645 Types: Broken Link
      —
      Reference typeremoved
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048797%2C2050536%2C2053272%2C2053579%2C2057115%2C2057116%2C2057130%2C2057991%2C2057995%2C2058002%2C2058008%2C2058032%2C2058102%2C2058667 Types: Broken Link
      —
      Reference typeremoved
      https://bugzilla.mozilla.org/show_bug.cgi?id=2059424 Types: Permissions Required
      —
      Reference typeremoved
      https://www.mozilla.org/security/advisories/mfsa2026-74/ Types: Vendor Advisory
      —
      Reference typeremoved
      https://www.mozilla.org/security/advisories/mfsa2026-76/ Types: Vendor Advisory
      —
      Reference typeremoved
      https://www.mozilla.org/security/advisories/mfsa2026-77/ Types: Vendor Advisory
      —
      Reference typeremoved
      https://www.mozilla.org/security/advisories/mfsa2026-78/ Types: Vendor Advisory
      —
      Reference typeremoved
      https://www.mozilla.org/security/advisories/mfsa2026-79/ Types: Vendor Advisory
      —
      Reference typeremoved
      https://www.mozilla.org/security/advisories/mfsa2026-80/ Types: Vendor Advisory
      —

      Source identifier: security@mozilla.org

    3. Record modifiedMozilla

      Description added or changed

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionchanged
      Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
      Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

      Source identifier: security@mozilla.org

    4. Initial analysis by NVDNVD

      Newly listed as affected:
      Show 10 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Product configurationadded
      —
      OR *cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* versions from (including) 141.0 up to (excluding) 153.1.0 *cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* versions from (including) 141.0 up to (excluding) 153.1.0 *cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* versions up to (excluding) 140.14.0 *cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* versions up to (excluding) 140.14.0
      Reference typeadded
      —
      Mozilla Corporation: https://bugzilla.mozilla.org/buglist.cgi?bug_id=1500946%2C1788109%2C2045379%2C2045380%2C2049339%2C2049393%2C2053580%2C2054662%2C2054665%2C2054673%2C2054785%2C2058645 Types: Broken Link
      Reference typeadded
      —
      Mozilla Corporation: https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048797%2C2050536%2C2053272%2C2053579%2C2057115%2C2057116%2C2057130%2C2057991%2C2057995%2C2058002%2C2058008%2C2058032%2C2058102%2C2058667 Types: Broken Link
      Reference typeadded
      —
      Mozilla Corporation: https://bugzilla.mozilla.org/show_bug.cgi?id=2059424 Types: Permissions Required
      Reference typeadded
      —
      Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-74/ Types: Vendor Advisory
      Reference typeadded
      —
      Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-76/ Types: Vendor Advisory
      Reference typeadded
      —
      Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-77/ Types: Vendor Advisory
      Reference typeadded
      —
      Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-78/ Types: Vendor Advisory
      Reference typeadded
      —
      Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-79/ Types: Vendor Advisory
      Reference typeadded
      —
      Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-80/ Types: Vendor Advisory

      Source identifier: nvd@nist.gov

    5. Record modifiedCISA ADP

      CVSS V3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

      CISA assessment (SSVC): exploitation: none known, automatable: yes

      Weakness type: CWE-119

      Show 3 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      CVSSadded
      —
      AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
      Weakness type (CWE)added
      —
      CWE-119
      SSVC assessmentadded
      —
      {"id":"CVE-2026-74987","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"total"}],"version":"2.0.3","timestamp":"2026-08-19T13:05:41.543564Z"}

      Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Show one older change

    1. ReceivedMozilla

      Description added or changed

      Show 8 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      Firefox
      Descriptionadded
      —
      Internally found bugs present in Firefox ESR 140.13, Firefox ESR 153.0 and Firefox 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1.
      Referenceadded
      —
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=1500946%2C1788109%2C2045379%2C2045380%2C2049339%2C2049393%2C2053580%2C2054662%2C2054665%2C2054673%2C2054785%2C2058645
      Referenceadded
      —
      https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048797%2C2050536%2C2053272%2C2053579%2C2057115%2C2057116%2C2057130%2C2057991%2C2057995%2C2058002%2C2058008%2C2058032%2C2058102%2C2058667
      Referenceadded
      —
      https://bugzilla.mozilla.org/show_bug.cgi?id=2059424
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-74/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-76/
      Referenceadded
      —
      https://www.mozilla.org/security/advisories/mfsa2026-77/

      Source identifier: security@mozilla.org

    Linked CVEs

    Linked CVEs
    CriticalCVE-2026-75874Sandbox escape in the Remote Settings Client component10.0—
    CriticalCVE-2026-74990Mozilla Firefox: Memory Corruption9.8—
    CriticalCVE-2026-74989Internally found bugs fixed in Firefox 1549.8—
    CriticalCVE-2026-74988Internally found bugs fixed in Firefox ESR 153.1 and Firefox 1549.8—
    CriticalCVE-2026-74987Internally found bugs fixed in Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 1549.8—
    CriticalCVE-2026-74986Site isolation issue in the CSS Parsing and Computation component9.1—
    CriticalCVE-2026-74985Privilege escalation in the Enterprise Policies component9.8—
    MediumCVE-2026-74984Race condition in the JavaScript Engine component6.8—
    HighCVE-2026-74983Mitigation bypass in the Data Loss Prevention component8.1—
    HighCVE-2026-74982Denial-of-service in the Widget component7.5—
    HighCVE-2026-74981Site isolation issue in the Audio/Video: Web Codecs component8.1—
    MediumCVE-2026-74980Clickjacking issue in the Downloads component in Firefox for Android6.5—
    CriticalCVE-2026-74979Mitigation bypass in the Add-ons Manager component9.8—
    HighCVE-2026-74978Clickjacking issue in the Widget component8.1—
    HighCVE-2026-74977Integer overflow in the Graphics component7.5—
    MediumCVE-2026-74976JIT miscompilation in the JavaScript Engine: JIT component6.5—
    MediumCVE-2026-74975Spoofing issue in the Downloads component in Firefox for Android5.4—
    MediumCVE-2026-74974Same-origin policy bypass in the Graphics: ImageLib component5.4—
    MediumCVE-2026-74973Race condition, use-after-free in the Graphics component4.2—
    MediumCVE-2026-74972Information disclosure in the DOM: Push Subscriptions component4.3—
    MediumCVE-2026-74971Information disclosure in the DOM: UI Events & Focus Handling component4.3—
    MediumCVE-2026-74970Site isolation issue in the Graphics component5.4—
    HighCVE-2026-74969Race condition, use-after-free in the Layout: Text and Fonts component8.8—
    MediumCVE-2026-74968Site isolation issue in the Graphics: WebRender component5.4—
    Show 34 more CVEs
    Linked CVEs
    MediumCVE-2026-74967Same-origin policy bypass in the Audio/Video: Playback component5.4—
    HighCVE-2026-74966Information disclosure in the Form Autofill component7.5—
    HighCVE-2026-74965Privilege escalation in the Shell Integration component8.8—
    CriticalCVE-2026-74964Integer overflow in the Graphics component9.8—
    MediumCVE-2026-74963Same-origin policy bypass in the Networking: Cookies component5.4—
    HighCVE-2026-74962Site isolation issue in the Networking: Cookies component8.1—
    CriticalCVE-2026-74961Side-channel in the Web Audio component9.1—
    HighCVE-2026-74960Site isolation issue in the WebExtensions component8.1—
    CriticalCVE-2026-74959Mitigation bypass in the Storage: Cache API component9.1—
    HighCVE-2026-74958Information disclosure in the WebRTC component7.5—
    HighCVE-2026-74957Mitigation bypass in the Safe Browsing component8.1—
    CriticalCVE-2026-74956Same-origin policy bypass in the DOM: Service Workers component9.1—
    HighCVE-2026-74955Privilege escalation in the Request Handling component8.8—
    HighCVE-2026-74954Information disclosure due to side-channel in the Storage: Cache API component7.5—
    HighCVE-2026-74953Privilege escalation in the Networking: Cookies component8.8—
    HighCVE-2026-74952Privilege escalation in the Application Update component8.8—
    MediumCVE-2026-74951Clickjacking issue in Firefox for Android6.5—
    HighCVE-2026-74950Privilege escalation in the Downloads API component8.8—
    HighCVE-2026-74949Use-after-free in the Graphics: Canvas2D component8.8—
    MediumCVE-2026-74948Information disclosure in the Graphics component6.5—
    HighCVE-2026-74947Privilege escalation due to invalid pointer in the Graphics component8.8—
    HighCVE-2026-74946Information disclosure due to incorrect boundary conditions in the Graphics: CanvasWebGL component8.8—
    MediumCVE-2026-74945Information disclosure in the Graphics: Text component6.5—
    CriticalCVE-2026-74944Use-after-free in the DOM: Core & HTML component9.8—
    CriticalCVE-2026-74943Use-after-free in the Graphics: ImageLib component9.8—
    HighCVE-2026-74942Privilege escalation in the Remote Settings Client component8.8—
    HighCVE-2026-74941Privilege escalation in the Graphics: CanvasWebGL component8.8—
    CriticalCVE-2026-74940Use-after-free in the Graphics: Text component9.8—
    HighCVE-2026-74939Privilege escalation in the DOM: Navigation component8.8—
    CriticalCVE-2026-74938Mitigation bypass in the JavaScript: GC component9.1—
    HighCVE-2026-74937Use-after-free in the JavaScript: GC component8.8—
    CriticalCVE-2026-74936Use-after-free in the JavaScript: WebAssembly component9.8—
    HighCVE-2026-74935Privilege escalation in the DOM: Networking component8.8—
    HighCVE-2026-74934Site isolation issue in the Graphics: CanvasWebGL component7.5—

    Linked advisories

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    Badge preview for CVE-2026-74987
    <a href="https://intel.neosec.eu/en/cve/CVE-2026-74987"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-74987.svg?lang=en" alt="CVE-2026-74987 – NEOSEC Intel" height="20"></a>