TIRESIS/Forecast/CVE-2026-21514
⚡ CISA KEV — Actively Exploited🔒 Ransomware-LinkedCRITICAL RISK

CVE-2026-21514

Reliance on untrusted inputs in a security decision in Microsoft Office Word allows an unauthorized attacker to bypass a security feature locally.

SMB Attack Probability Score
80/100critical
Weighted: EPSS · CISA KEV · SMB stack prevalence · exploit maturity · CVSS vector
CVSS v3
7.8
EPSS (30d)
5.14%
SMB Exposure
85.5/100
Attack Vector
LOCAL
Complexity
LOW
Privileges
NONE
📄
SMB Impact
How this vulnerability affects a real small business
1
How this breaks an SMB

Office productivity vulnerabilities (Word, Excel, Acrobat) are primary vectors for phishing-delivered malware — one opened file can compromise the entire company.

2
Typical real-world scenario

Malicious document arrives via email. Macro or exploit executes silently. Attacker gains persistent access to the employee's machine and credentials.

3
Estimated downtime & cost
Est. downtime
1–3 days
Business cost range
€5K–€30K
4
What IT should check this week
Are macros disabled by default in Office applications?
Is Adobe Acrobat/Reader updated to latest version?
Are employees trained to verify unexpected documents?
Is email attachment scanning active on mail gateway?
Scenarios are generated based on software category and CVE characteristics. Cost ranges reflect SMB incidents in TIRESIS incident database.
Threat Evolution Timeline
From disclosure to predicted exploitation — 7 events
◈ 1 predicted
📋
10 Feb 2026
Vulnerability disclosed
CVE published by NVD with CVSS 7.8 (HIGH)
🚨
10 Feb 2026CISA KEV
Added to CISA KEV catalog
CISA confirms active exploitation. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
⚡
12 Feb 2026
Exploit in the wild
Active exploitation observed — automated scanning and targeted attacks underway
🔒
13 Feb 2026Ransomware
Ransomware campaigns active
Groups using this vector: Conti. SMB targets observed.
🔬
24 Feb 2026
Proof-of-Concept published
Public PoC code available — exploitation now accessible to non-expert attackers
📍
TODAY
Today
EPSS: 5.1% probability of exploitation in next 30 days. SMB Risk Score: 80/100
Forecast →
✅
14 Aug 2026◈ predicted · in 60 days
Predicted: widespread patch adoption
Low EPSS suggests limited active exploitation. Most organizations expected to patch in routine maintenance cycle.
◈ Predicted eventsare estimates based on EPSS score, exploit maturity, and historical CVE progression patterns. They are not guaranteed outcomes.
Affected Products
office long term servicing channel365 apps
Remediation & References
⚡ CISA Required Action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Federal agency patch deadline: 2026-03-03
What to do
🚨Patch immediately — actively exploited in the wildcritical

CISA has confirmed exploitation of this vulnerability. Federal agencies must patch within the KEV deadline. SMBs should treat this as P0: patch or mitigate within 24–48 hours.

🎣Raise user awareness — this can be triggered via phishingmedium

Exploitation requires user interaction (e.g., opening a file, clicking a link). While patching is the definitive fix, remind users not to open unexpected attachments or links. This type of vulnerability is commonly chained with phishing campaigns targeting SMBs.

💻Local access required — review endpoint hardeninglow

An attacker needs local access to exploit this. Focus on endpoint detection, privilege management, and preventing initial compromise (phishing, malicious USB).

Official Patch & Advisory Sources
NVD Full Entry ↗Official vulnerability detail, CVSS vectors, CPE listCISA KEV Entry ↗CISA Known Exploited Vulnerabilities catalogEPSS Score ↗Exploit Prediction Scoring System — FIRST.orgMitre CVE ↗MITRE CVE Program official entry
Vendor & Exploit References
Scoring Methodology

SMB Attack Probability Score weights: EPSS exploit likelihood (35%), CISA KEV active exploitation (25%), SMB stack prevalence (20%), exploit maturity (10%), CVSS network vector complexity (10%). Impact scenarios are derived from software category and historical SMB incident patterns. Scores recompute daily.