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Threats / Spreadsheet::ParseExcel / CVE-2023-7101
CVE-2023-7101 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Spreadsheet::ParseExcel vulnerability

Spreadsheet::ParseExcel contains a remote code execution vulnerability through unsafe evaluation of Number format strings from Excel files, allowing arbitrary code execution when processing malicious spreadsheets.

Verdict

Today item — known-exploited.

An attacker can craft a malicious Excel file with specially formatted Number strings that, when parsed by Spreadsheet::ParseExcel, execute arbitrary code on the victim's system. This vulnerability is actively exploited in the wild.

CISA KEV Yes · 2024-01-023EPSS 0.167 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
2 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-01-02).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.167 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Spreadsheet::ParseExcel, Spreadsheet::ParseExcel. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-95 Eval Injection — weakness family: Injection.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-95 · Eval InjectionInjection
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
Craft a malicious Excel file embedding code in Number format strings.
Business
Attacker gains arbitrary code execution on systems processing the file.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
Distribute the file via email, file sharing, or compromised websites.
Business
Victim organization's systems become compromised without user awareness of the threat.
3

Lateral reach — past segmentation narrative 3

Attacker
Execute post-exploitation activities including data exfiltration or lateral movement.
Business
Sensitive data is stolen or internal systems are further compromised, escalating business impact.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • 2 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by Mandiant (CNA)
  • Named finder/reporter credit (CVE.org)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • Disclosure & credit2
    Catalogued by MandiantCNA
    Credited with finding itLe Dinh Hai (https://github.com/haile01/perl_spreadsheet_excel_rce_poc/tree/main)finderBarracuda Networks Inc. https://www.barracuda.com/reporter