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Vulnerabilities/CVE-2026-108457Public Intelligence Dossier
Source: Microsoft · Limited verification•Last verified: •Collection Degraded
CVE-2026-108457Unknown / EvaluatingCritical (raw)CVSS 8.1CWE-787

Microsoft Windows PDF Remote Code Execution Vulnerability

Published: 13 Oct 2026•Last updated: 13 Oct 2026, 12:30 PM IST•Source identifier: secure@microsoft.com
Dossier completeness: source-provided sections 3 / 3 · rule guidance available. Missing source facts count as incomplete.
Official source
CISA KEV catalog
Unknown
KEV status was not determined.
CVSS score
8.1Critical (raw)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Metric sourceMicrosoft MSRC CVRF
EPSS probability
0.7%0.007
Percentile52nd
Weakness type
CWE-787
No further CWE recorded
Remediation
Patch status unknown
KB5126653, KB5126657, KB5126655, KB5126646

Why It Matters

Analysis dossier

Why It Matters

Out-of-bounds write in Microsoft Windows PDF allows an unauthorized attacker to execute code over a network.

SOC priority

High

Actively exploited

No

Publicly disclosed

Unknown

Risk basis: Microsoft or Microsoft-managed product relevance; HIGH severity; No confirmed exploitation signal in current enrichment

Affected Products & Remediation

12 source-backed products
Affected products and versions (source)
  • Windows 11 Version 23H2 for x64-based Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows 10 Version 21H2 for ARM64-based Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows 10 Version 22H2 for x64-based Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows Server 2022 (Server Core installation) · version range not provided by source · Microsoft MSRC · Source
  • Windows Server 2022 · version range not provided by source · Microsoft MSRC · Source
  • Windows 10 Version 21H2 for x64-based Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows 11 Version 23H2 for ARM64-based Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows 10 Version 21H2 for 32-bit Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows Server 2025 (Server Core installation) · version range not provided by source · Microsoft MSRC · Source
  • Windows Server 2025 · version range not provided by source · Microsoft MSRC · Source
  • Windows 10 Version 22H2 for ARM64-based Systems · version range not provided by source · Microsoft MSRC · Source
  • Windows 10 Version 22H2 for 32-bit Systems · version range not provided by source · Microsoft MSRC · Source
Recorded patch / KBKB5126653, KB5126657, KB5126655, KB5126646

Vendor or catalog guidance (source)

  • Microsoft MSRC: Install the security update KB5126653 listed by MSRC
  • Microsoft MSRC: Install the security update KB5126657 listed by MSRC
  • Microsoft MSRC: Install the security update KB5126655 listed by MSRC
  • Microsoft MSRC: Install the security update KB5126646 listed by MSRC

Known exploitation (source facts)

Only what a source states. Unknown means no source has said either way; it is not "not exploited".

CISA KEV
Unknown
Exploited (source statement)
No
Publicly disclosed (source)
Unknown

Suggested hunting (rule-based inference)

SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.

Matched microsoft-enterprise (Affected product: Windows 11 Version 23H2 for x64-based Systems, Vendor: Microsoft); network-unauthenticated (CVSS AV:N, CVSS PR:N, CVSS UI:N)

Exposure

  1. Identify affected Microsoft products and compare local builds with the MSRC advisory.Telemetry: DeviceTvmSoftwareVulnerabilities · The MSRC product/build mapping establishes applicability. · Rule microsoft-enterprise
  2. Identify devices reporting this CVE and note which expose the affected service to untrusted networks.Telemetry: DeviceTvmSoftwareVulnerabilities · A network-reachable, no-privilege vector makes internet-facing instances the first exposure question. · Rule network-unauthenticated

Exploitation evidence

  1. Review the advisory's documented behavior on matching hosts before selecting a hunt.Telemetry: DeviceProcessEvents · Product family alone does not justify a CVE-specific detection. · Rule microsoft-enterprise
Show more (2)

Exploitation evidence

  1. Review inbound connections to the affected service from unexpected sources since the advisory date.Telemetry: DeviceNetworkEvents · Hunting hypothesis from the CVSS vector; it does not show that exploitation occurred. · Rule network-unauthenticated

Response

  1. Confirm the source-stated KB or mitigation on matching assets.Telemetry: DeviceTvmSoftwareVulnerabilities · A post-update inventory check verifies remediation. · Rule microsoft-enterprise

CISA KEV Record

CISA KEV status was not determined for this record.

Change History & Source Data

— No recorded material change

CNA / source
secure@microsoft.com
Record status · verification
UPDATED · Unknown
CPE
Unknown

Evidence & Provenance

3 public sources
api.msrc.microsoft.comSource recordnvd.nist.govSource recordmsrc.microsoft.comSource record
Detection Hunting Query

— No published hunting query names this record. Browse community and library queries instead.

Open KQL Library

Correlated briefings

Microsoft Security Update Guide · Limited verificationOctober 2026 Security UpdatesPublished 13 Oct 2026
SecOps Signal surfaces public advisory facts only. A missing value means the source has not published it, not that your environment is unaffected. No tenant inventory is connected.