BlackTreeCVE Intelligence
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Full vulnerability report · 2026
CVE-2026-87707High confidence

Windows Fax and Scan Service Elevation of Privilege Vulnerability

Microsoft · Windows 10 Version 1607

7.8HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:Medium, lowered one band.downgradedsince 13 Oct 2026

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.24% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Microsoft Windows 10 Version 1607 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: As exposure requiresRemediation target: Within 365 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.

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-2026-99640

No EUVD known-exploited evidence

Heap-based buffer overflow in Windows Fax and Scan Service allows an authorized attacker to elevate privileges locally.

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
7.8 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

Heap-based buffer overflow in Windows Fax and Scan Service allows an authorized attacker to elevate privileges locally.

What

Heap-based buffer overflow in Windows Fax and Scan Service allows an authorized attacker to elevate privileges locally.

Why

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.

What

Heap-based buffer overflow in Windows Fax and Scan Service allows an authorized attacker to elevate privileges locally.

Why

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.

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
local access → Heap-based Buffer Overflow → gain additional privileges
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
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-122 ↗

CWE-122: Heap-based Buffer Overflow. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

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

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

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level 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.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
Privilege escalationCWE-122
A

Official authority intelligence

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

ENISA EUVD · EUVD-2026-99640Official EUVD mapping

Heap-based buffer overflow in Windows Fax and Scan Service allows an authorized attacker to elevate privileges locally.

Official EUVD record ↗
BSI · German · WID-SEC-2026-3892Microsoft Windows und Windows Server: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in verschiedenen Versionen von Microsoft Windows Server und Microsoft Windows ausnutzen, um seine Privilegien auf administrative Rechte zu erhöhen, um beliebigen Code auszuführen, um Informationen offenzulegen, um einen Denial of Service herbeizuführen, um den Benutzer zu täuschen und andere, nicht näher spezifizierte Auswirkungen zu verursachen.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-1314Avis du CERT-FR

6-87693 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87694 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87698 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87699 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87700 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87702 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87704 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87705 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87706 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87707 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87708 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87709 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87710 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87711 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87712 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87713 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87714 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-2026-87715 du 13 octobre 2026 Bulletin de sécurité Microsoft Windows CVE-202

Official advisory ↗
CSIRT Italia · Italian · aggiornamenti-mensili-microsoft-25Aggiornamenti Mensili Microsoft

finestra - - CVE-2026-85792 : apre una nuova finestra - - CVE-2026-85791 : apre una nuova finestra - - CVE-2026-83931 : apre una nuova finestra - - CVE-2026-85318 : apre una nuova finestra - - CVE-2026-83932 : apre una nuova finestra - - CVE-2026-83934 : apre una nuova finestra - - CVE-2026-85319 : apre una nuova finestra - - CVE-2026-85798 : apre una nuova finestra - - CVE-2026-83930 : apre una nuova finestra - - CVE-2026-85799 : apre una nuova finestra - - CVE-2026-87708 : apre una nuova finestra - - CVE-2026-85881 : apre una nuova finestra - - CVE-2026-85884 : apre una nuova finestra Presente - CVE-2026-87706 : apre una nuova finestra - - CVE-2026-87707 : apre una nuova finestra - - CVE-2026-87704 : apre una nuova finestra - - CVE-2026-87705 : apre una nuova finestra - - CVE-2026-85886 : apre una nuova finestra - - CVE-2026-87702 : apre una nuova finestra - - CVE-2026-85888 : apre una nuova finestra - - CVE-2026-87700 : apre una nuova finestra - - CVE-2026-83918 : apre una nuova finestra - - CVE-2026-83919 : apre una nuova finestra - - CVE-2026-87710 : apre una nuova finestra - - CVE-2026-85891 : apre una nuova finestra - - CVE-2026-87715 : apre una nuova finestra - - CVE-2026-87716 : apre una nuova finestra - - CVE-2026-87713 : apre una nuova finestra - - CVE-2026-87711 : apre una nuova fi

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-6991MS 10월 보안 위협에 따른 정기 보안 업데이트 권고

e 권한 상승 취약성 | | Windows USB Driver | CVE-2026-85935 | Windows USB Driver 정보 유출 취약성 | | Windows Shell | CVE-2026-85936 | Windows Shell 원격 코드 실행 취약성 | | Windows Broadcast DVR User Service | CVE-2026-85938 | Windows Broadcast DVR User Service 정보 유출 취약성 | | Windows Kernel | CVE-2026-85939 | Windows Kernel 보안 기능 우회 취약성 | | Windows Kernel | CVE-2026-85945 | Windows Kernel 권한 상승 취약성 | | Windows Management Services | CVE-2026-87691 | Windows Management Services 권한 상승 취약성 | | .NET | CVE-2026-87697 | .NET 원격 코드 실행 취약성 | | Windows Storage Spaces Controller | CVE-2026-87706 | Windows Storage Spaces Controller 권한 상승 취약성 | | Windows Fax and Scan Service | CVE-2026-87707 | Windows Fax and Scan Service 권한 상승 취약성 | | Windows Installer | CVE-2026-87708 | Windows Installer 권한 상승 취약성 | | Microsoft Local Security Authority Server (lsasrv) | CVE-2026-87710 | Microsoft Local Security Authority (LSA) Server 권한 상승 취약성 | | Windows Installer | CVE-2026-87711 | Windows Installer 권한 상승 취약성 | | Windows Quality of Service (QoS) Packet Scheduler | CVE-2026-87712 | Microsoft Windows QoS Scheduler Driver 권한 상승 취약성 | | Windows Bluetooth Port Driver | CVE-2026-87713 | Windows Bluetooth Port Driver 원격 코드 실행 | | WebDAV | CVE-2026-87714 | WebDAV 보안 기능 우회 취약성 | | Windows Storage Spaces Controller | CVE-2026-87716 | Windows Storage S

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.
Patch available
Affected
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
Official vendor articles10 stored documents

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.

04

Evidence and provenance

Published 13 Oct 2026 · Last source change 28 Oct 2026, 18:14 UTC · CWE-122 · Heap-based Buffer Overflow

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-10-14
European sourceENISA EUVD · EUVD-2026-99640
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceOther authority
NVD statusNVD awaiting enrichment

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

Material change intelligence

What changed after publication

View recent updates ↗
  1. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  2. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  3. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  4. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  5. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  6. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  7. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  8. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  9. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  10. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  11. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  12. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  13. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  14. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  15. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  16. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  17. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  18. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  19. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  20. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  21. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  22. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  23. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  24. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  25. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  26. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  27. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  28. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  29. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  30. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  31. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  32. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  33. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  34. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  35. Vendor guidanceAuthoritative vendor guidance changed: removed remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25.
    Before
    remediation: acn.gov.it/aggiornamenti-mensili-microsoft-25
    After
    no authoritative guidance recorded
    CNA ↗
  36. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  37. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    CSIRT Italia ↗
  38. ENISA EUVD mappingEUVD-2026-99640 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-99640"}
    ENISA EUVD ↗
  39. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
  40. CVSS scoreCVSS vector changed while the displayed base score remained 7.8.
    Before
    7.8 (CVSS 3.1 · CNA · CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
    After
    7.8 (CVSS 3.1 · CNA · CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C)
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Remediation guidance recorded
ENISA EUVD · EUVD-2026-99640↗CSIRT Italia remediation guidance↗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-2026-87707 · cve.blacktree.nl