BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2026
CVE-2026-100763High confidence

Incorrect boundary conditions in the Graphics: WebGPU component

Mozilla · Thunderbird

9.1CriticalCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 164 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 0.40% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Mozilla Thunderbird and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 164 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

3 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian sidsid · sourcefirefoxVendor fix publishedDebian records a fixed source-package version for this release.157.0-1Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivemozjs102Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 4 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivemozjs115Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 4 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-100763 · CSAF 2.0 · revision 4 · interimSUSE Product Security TeamCVE-2026-100763
164 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • MozillaFirefox as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaFirefox-devel as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaFirefox-translations-common as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaFirefox-translations-other as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaThunderbird as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaThunderbird-translations-common as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaThunderbird-translations-other as component of SUSE Linux Enterprise Desktop 15 SP7
  • MozillaFirefox as component of SUSE Linux Enterprise High Performance Computing 12 SP5
  • MozillaFirefox-devel as component of SUSE Linux Enterprise High Performance Computing 12 SP5
  • MozillaFirefox-translations-common as component of SUSE Linux Enterprise High Performance Computing 12 SP5
  • MozillaFirefox as component of SUSE Linux Enterprise High Performance Computing 15 SP1
  • MozillaFirefox-devel as component of SUSE Linux Enterprise High Performance Computing 15 SP1
Summary
Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.
Remediation
No remediation text is recorded.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-88915

No EUVD known-exploited evidence

Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
9.1 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 164 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

What

Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

Why

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.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

Why

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.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Restriction of Operations within the Bounds of a Memory Buffer → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-119 ↗

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

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-119
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-88915Official EUVD mapping

Incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

Official EUVD record ↗
BSI · German · WID-SEC-2026-3654Mozilla Firefox, Firefox ESR und Thunderbird: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Mozilla Firefox ESR, Mozilla Firefox und Thunderbird ausnutzen, um beliebigen Programmcode auszuführen, Berechtigungen zu erweitern, Sicherheitsmaßnahmen zu umgehen, Daten offenzulegen oder zu manipulieren, einen Denial-of-Service-Zustand auszulösen oder andere, nicht näher spezifizierte Angriffe zu starten.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-1244Multiples vulnérabilités dans Mozilla Thunderbird

30 septembre 2026 https://www.mozilla.org/en-US/security/advisories/mfsa2026-103/ Référence CVE CVE-2026-100756 https://www.cve.org/CVERecord?id=CVE-2026-100756 Référence CVE CVE-2026-100757 https://www.cve.org/CVERecord?id=CVE-2026-100757 Référence CVE CVE-2026-100758 https://www.cve.org/CVERecord?id=CVE-2026-100758 Référence CVE CVE-2026-100759 https://www.cve.org/CVERecord?id=CVE-2026-100759 Référence CVE CVE-2026-100760 https://www.cve.org/CVERecord?id=CVE-2026-100760 Référence CVE CVE-2026-100761 https://www.cve.org/CVERecord?id=CVE-2026-100761 Référence CVE CVE-2026-100762 https://www.cve.org/CVERecord?id=CVE-2026-100762 Référence CVE CVE-2026-100763 https://www.cve.org/CVERecord?id=CVE-2026-100763 Référence CVE CVE-2026-100764 https://www.cve.org/CVERecord?id=CVE-2026-100764 Référence CVE CVE-2026-100765 https://www.cve.org/CVERecord?id=CVE-2026-100765 Référence CVE CVE-2026-100766 https://www.cve.org/CVERecord?id=CVE-2026-100766 Référence CVE CVE-2026-100767 https://www.cve.org/CVERecord?id=CVE-2026-100767 Référence CVE CVE-2026-100768 https://www.cve.org/CVERecord?id=CVE-2026-100768 Référence CVE CVE-2026-100769 https://www.cve.org/CVERecord?id=CVE-2026-100769 Référence CVE CVE-2026-100770 https://www.cve.org/CVERecord?id=CVE-2026-100770 Référence CVE CVE-2026-100771 https://www.cve.o

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-1240Multiples vulnérabilités dans les produits Mozilla

u 29 septembre 2026 https://www.mozilla.org/en-US/security/advisories/mfsa2026-99/ Référence CVE CVE-2026-100756 https://www.cve.org/CVERecord?id=CVE-2026-100756 Référence CVE CVE-2026-100757 https://www.cve.org/CVERecord?id=CVE-2026-100757 Référence CVE CVE-2026-100758 https://www.cve.org/CVERecord?id=CVE-2026-100758 Référence CVE CVE-2026-100759 https://www.cve.org/CVERecord?id=CVE-2026-100759 Référence CVE CVE-2026-100760 https://www.cve.org/CVERecord?id=CVE-2026-100760 Référence CVE CVE-2026-100761 https://www.cve.org/CVERecord?id=CVE-2026-100761 Référence CVE CVE-2026-100762 https://www.cve.org/CVERecord?id=CVE-2026-100762 Référence CVE CVE-2026-100763 https://www.cve.org/CVERecord?id=CVE-2026-100763 Référence CVE CVE-2026-100764 https://www.cve.org/CVERecord?id=CVE-2026-100764 Référence CVE CVE-2026-100765 https://www.cve.org/CVERecord?id=CVE-2026-100765 Référence CVE CVE-2026-100766 https://www.cve.org/CVERecord?id=CVE-2026-100766 Référence CVE CVE-2026-100767 https://www.cve.org/CVERecord?id=CVE-2026-100767 Référence CVE CVE-2026-100768 https://www.cve.org/CVERecord?id=CVE-2026-100768 Référence CVE CVE-2026-100769 https://www.cve.org/CVERecord?id=CVE-2026-100769 Référence CVE CVE-2026-100770 https://www.cve.org/CVERecord?id=CVE-2026-100770 Référence CVE CVE-2026-100771 https://www.cve.o

Official advisory ↗
CSIRT Italia · Italian · risolte-vulnerabilita-in-prodotti-mozilla-11Risolte vulnerabilità in prodotti Mozilla

a - - CVE-2026-100777 : apre una nuova finestra - - CVE-2026-100776 : apre una nuova finestra - - CVE-2026-100775 : apre una nuova finestra - - CVE-2026-100774 : apre una nuova finestra - - CVE-2026-100773 : apre una nuova finestra - - CVE-2026-100772 : apre una nuova finestra - - CVE-2026-100771 : apre una nuova finestra - - CVE-2026-100770 : apre una nuova finestra - - CVE-2026-100769 : apre una nuova finestra - - CVE-2026-100768 : apre una nuova finestra - - CVE-2026-100767 : apre una nuova finestra - - CVE-2026-100766 : apre una nuova finestra - - CVE-2026-100765 : apre una nuova finestra - - CVE-2026-100764 : apre una nuova finestra - - CVE-2026-100763 : apre una nuova finestra - - CVE-2026-100762 : apre una nuova finestra - - CVE-2026-100761 : apre una nuova finestra - - CVE-2026-100760 : apre una nuova finestra - - CVE-2026-100759 : apre una nuova finestra - - CVE-2026-100758 : apre una nuova finestra - - CVE-2026-100757 : apre una nuova finestra - - CVE-2026-100756 : apre una nuova finestra - - Riferimenti (7) https://www.mozilla.org/en-US/security/advisories/mfsa2026-97/ https://www.mozilla.org/en-US/security/advisories/mfsa2026-98/ https://www.mozilla.org/en-US/security/advisories/mfsa2026-99/ https://www.mozilla.org/en-US/security/advisories/mfsa2026-100/ https://www.mozilla.org/en-U

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
Fixed
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
Official vendor articles1 stored document

Linked articles are downloaded and versioned as source evidence. A CVE mention or approved update relationship does not, by itself, verify a fix for every product branch.

  • Security Vulnerabilities fixed in Firefox 157 — Mozilla →Original publisher ↗Searchable text snapshot · Captured 29 Sep 2026Security Vulnerabilities fixed in Firefox 157 Announced September 29, 2026 Impact high Products Firefox Fixed in Firefox 157 Note : We have changed how we publish advisories. We no longer roll all internally identified memory safety vulnerabilities into a single CVE and are now issuing an advisory for every indi
04

Evidence and provenance

Published 29 Sept 2026 · Last source change 1 Oct 2026, 14:37 UTC · CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer

CVE recordCVE.org · 5.2
CVSS sourceCISA ADP
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-09-30
European sourceENISA EUVD · EUVD-2026-88915
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceCVE/CNA references
CWE sourceCISA ADP
NVD statusNVD enrichment underway

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. SeveritySeverity changed from Unknown to Critical.
    Before
    Unknown
    After
    Critical
    CISA ADP ↗
  2. CVSS scoreCVSS score changed from not recorded to 9.1 (CVSS 3.1 · CISA ADP · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H).
    Before
    not recorded
    After
    9.1 (CVSS 3.1 · CISA ADP · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H)
    CISA ADP ↗
  3. Vendor guidanceAuthoritative vendor guidance changed: added remediation: bugzilla.mozilla.org/show_bug.cgi?id=2059929; removed remediation: mozilla.org/mfsa2026-101.
    Before
    remediation: mozilla.org/mfsa2026-101
    After
    remediation: bugzilla.mozilla.org/show_bug.cgi?id=2059929
    CNA ↗
  4. Vendor guidanceAuthoritative vendor guidance changed: added remediation: mozilla.org/mfsa2026-101; removed remediation: bugzilla.mozilla.org/show_bug.cgi?id=2059929.
    Before
    remediation: bugzilla.mozilla.org/show_bug.cgi?id=2059929
    After
    remediation: mozilla.org/mfsa2026-101
    CNA ↗
  5. Affected versionsThe structured affected or fixed version information changed.
    Before
    See the vendor and CVE records for the affected range. · Fixed: Firefox: 157 ≤ *
    After
    See the vendor and CVE records for the affected range. · Fixed: Thunderbird: 157 ≤ *; Firefox: 157 ≤ *
    CNA ↗
  6. ENISA EUVD mappingEUVD-2026-88915 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-88915"}
    ENISA EUVD ↗
  7. Vendor guidanceAuthoritative vendor guidance changed: added remediation: bugzilla.mozilla.org/show_bug.cgi?id=2059929; removed patch: mozilla.org/mfsa2026-97; removed remediation: mozilla.org/mfsa2026-97.
    Before
    patch: mozilla.org/mfsa2026-97 · remediation: mozilla.org/mfsa2026-97
    After
    remediation: bugzilla.mozilla.org/show_bug.cgi?id=2059929
    CNA ↗
  8. Affected versionsThe structured affected or fixed version information changed.
    Before
    See the linked Mozilla advisory for the product-specific affected versions. · Fixed: Firefox 157
    After
    See the vendor and CVE records for the affected range. · Fixed: Firefox: 157 ≤ *
    CNA ↗
  9. SeveritySeverity changed from High to Unknown.
    Before
    High
    After
    Unknown
    CVE.org ↗
  10. Catalogue recordCVE added to the BlackTree catalogue.
    Authoritative vendor security advisory ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2026-88915↗Vendor CSAF · SUSE Product Security Team↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-100763 · cve.blacktree.nl