CVE-2009-3103
CriticalExploitedPublic exploitArray index error in the SMBv2 protocol implementation in srv2.sys in Microsoft Windows Vista Gold, SP1, and SP2, Windows Server 2008 Gold and SP2, and Windows 7 RC allows remote attackers to execute arbitrary code or cause a denial of service (system crash) via an & (ampersand)…
Published Sep 8, 2009 · Updated Apr 22, 2026
Key Facts
Patch immediately- CVE-2009-3103 is a critical-severity vulnerability (CVSS 10.0 v2) affecting Windows Server 2008 (Microsoft), Windows Vista (Microsoft).
- It is exploited in the wild, listed in Industry KEV feed since Jun 20, 2017 and is known to be used in ransomware campaigns. Public exploit code is available.
- EPSS estimates a 92% 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 it is listed as exploited in the wild.
CVSS v2
10.0
AV:N/AC:L/Au:N/C:C/I:C/A:C
EPSS (30-day exploit likelihood)
92%
Higher than 99.8% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing, used by ransomware
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2009-3103 brief as a PDF
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Description
Array index error in the SMBv2 protocol implementation in srv2.sys in Microsoft Windows Vista Gold, SP1, and SP2, Windows Server 2008 Gold and SP2, and Windows 7 RC allows remote attackers to execute arbitrary code or cause a denial of service (system crash) via an & (ampersand) character in a Process ID High header field in a NEGOTIATE PROTOCOL REQUEST packet, which triggers an attempted dereference of an out-of-bounds memory location, aka "SMBv2 Negotiation Vulnerability." NOTE: some of these details are obtained from third party information.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Jun 20, 2017 | n/a | Known |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
10 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Windows Server 2008Microsoft | sp2-x32, sp2-x64 | n/a |
| Windows VistaMicrosoft | See advisory | n/a |
Timeline
Publicly disclosed
Sep 8, 2009
Added to Industry KEV feed
Jun 20, 2017
Last updated
Apr 22, 2026
Weakness Type
- CWE-399
References
- advisory36623
- advisoryhttp://www.microsoft.com/technet/security/advisory/975497.mspx
- exploit20090907 Windows Vista/7 : SMB2.0 NEGOTIATE PROTOCOL REQUEST Remote B.S.O.D.
- exploithttp://g-laurent.blogspot.com/2009/09/windows-vista7-smb20-negotiate-protocol.html
- exploitVulnCheck exploitation report
FAQ
Common Questions.
Array index error in the SMBv2 protocol implementation in srv2.sys in Microsoft Windows Vista Gold, SP1, and SP2, Windows Server 2008 Gold and SP2, and Windows 7 RC allows remote attackers to execute arbitrary code or cause a denial of service (system crash) via an & (ampersand) character in a Process ID High header f…
Affected: Windows Server 2008 (Microsoft) versions sp2-x32, sp2-x64; Windows Vista (Microsoft). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Jun 20, 2017 and is known to be used in ransomware campaigns.
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 it is listed as exploited in the wild.
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