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Vulnerabilities/CVE-2026-107221Public Intelligence Dossier
Source: excelize · Limited verification•Last verified: •Collection Degraded
CVE-2026-107221Unknown / EvaluatingMEDIUM (raw)CVSS 6.5CWE-787

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets

Published: 08 Oct 2026•Last updated: 13 Oct 2026, 07:52 PM IST•Source identifier: security-advisories@github.com
Dossier completeness: source-provided sections 2 / 3 · rule guidance available. Missing source facts count as incomplete.
Official source
CISA KEV catalog
Unknown
KEV status was not determined.
CVSS score
6.5MEDIUM (raw)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Metric sourcesecurity-advisories@github.com
EPSS probability
0.3%0.003
Percentile18th
Weakness type
CWE-787
No further CWE recorded
Remediation
Patch status unknown
No fixed version or KB recorded

Why It Matters

Analysis dossier

Why It Matters

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.0.0 to 2.11.0, checkRow sizes its target cell slice from the last cell in XML document order and then re-scatters every cell by its explicit column reference. GetCellValue reaches workSheetReader and checkRow, where targetList is too short for an earlier out-of-order cell. When a crafted row places a higher-column cell before a lower-column final cell and a non-streaming worksheet API reads the sheet, the earlier cell's column index exceeds the slice length derived from the final cell, allowing an attacker to cause an unrecovered panic and terminate the process. No fixed version is available as of this review.

SOC priority

Medium

Actively exploited

Unknown

Publicly disclosed

Unknown

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

Affected Products & Remediation

1 source-backed product
Affected products and versions (source)
  • excelize excelize · >= 2.0.0 <= 2.11.0 · NVD CPE · Source
Recorded patch / KBNot provided by source

Vendor or catalog guidance (source)

Not provided by source

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)
Unknown
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 user-interaction-client (CVSS AV:N, CVSS UI:R)

Exposure

  1. Identify endpoints reporting this CVE, especially those used for email and web browsing.Telemetry: DeviceTvmSoftwareVulnerabilities · A network vector that needs user interaction points at user-facing client software. · Rule user-interaction-client

Exploitation evidence

  1. Review unusual child processes started by the affected client application on affected endpoints.Telemetry: DeviceProcessEvents · Hunting hypothesis from the CVSS vector; it does not show that exploitation occurred. · Rule user-interaction-client

Response

  1. Confirm the source-stated update on affected endpoints.Telemetry: DeviceTvmSoftwareVulnerabilities · A follow-up inventory check verifies remediation. · Rule user-interaction-client

CISA KEV Record

CISA KEV status was not determined for this record.

Change History & Source Data

— No recorded material change

CNA / source
security-advisories@github.com
Record status · verification
UPDATED · NVD API
CPE
cpe:2.3:a:excelize:excelize:*:*:*:*:*:go:*:*

Evidence & Provenance

3 public sources
github.comSource recordnvd.nist.govSource recordgithub.comSource record

Linked by the query's stored exact CVE association. Review required tables and validation status before use.

Detection Hunting Query
Target: DeviceTvmSoftwareVulnerabilities•Defender XDR
Detect endpoints exposed to CVE-2026-107221
Purpose: Exposure assessment (Category: Exposure Check)Why linked: Query metadata names CVE-2026-107221
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2026-107221"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel desc
Schema Checked · Not runtime validatedSource: SecOps Signal deterministic template · Limited verificationStatic screening: Passed structure and schema checks; tenant execution is not verified.
Open KQL Library

Correlated briefings

— No published briefing references this CVE

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.