CVE-2006-3431Excel Vulnerability
Buffer overflow in certain Asian language versions of Microsoft Excel might allow user-assisted attackers to execute arbitrary code via a crafted STYLE record in a spreadsheet that triggers the overflow when the user attempts to repair the document or selects the "Style" option,…
Published Jul 7, 2006 · Updated Apr 15, 2026
Key Facts
Patch immediately- CVE-2006-3431 is a high-severity vulnerability (CVSS 7.5 v2) affecting Excel (Microsoft).
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 28% probability of exploitation in the next 30 days.
- No fixed version is listed yet; check the vendor advisory for mitigations.
- Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
Scores
CVSS v2
7.5
AV:N/AC:L/Au:N/C:P/I:P/A:P
EPSS (30-day exploit likelihood)
28%
Higher than 98.1% of all scored CVEs
Exploit maturity
Proof of concept
ATLAS score
35/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Proof of concept
Public exploit code
1
Proof-of-concept links
In-the-wild evidence
1
Reports of active use
Advisories And Exploit References
- advisory20268
Description
Buffer overflow in certain Asian language versions of Microsoft Excel might allow user-assisted attackers to execute arbitrary code via a crafted STYLE record in a spreadsheet that triggers the overflow when the user attempts to repair the document or selects the "Style" option, as demonstrated by nanika.xls.
NOTE: Microsoft has confirmed to CVE via e-mail that this is different than the other Excel vulnerabilities announced before 20060707, including CVE-2006-3059 and CVE-2006-3086.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ExcelMicrosoft | See advisory | n/a |
Timeline
Publicly disclosed
Jul 7, 2006
Last updated
Apr 15, 2026
References
- advisory20268
- exploitExploitDB-28189
- exploit18872
- other20060711 New CVE number states Excel Style handling as a separate issue
- otherMS06-059
FAQ
Common Questions.
Buffer overflow in certain Asian language versions of Microsoft Excel might allow user-assisted attackers to execute arbitrary code via a crafted STYLE record in a spreadsheet that triggers the overflow when the user attempts to repair the document or selects the "Style" option, as demonstrated by nanika.xls.
Affected: Excel (Microsoft). The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
Is CVE-2006-3431 On Your Attack Surface?
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