Microsoft Windows Authenticode Signature Verification Remote Code Execution Vulnerability (CVE-2012-0151)
Published In CISA KEV since Sources: CVE.org
What is affected, what to do
The Authenticode Signature Verification function in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, Windows 7 Gold and SP1, and Windows 8 Consumer Preview does not properly validate the digest of a signed portable executable (PE) file, which allows user-assisted remote attackers to execute arbitrary code via a modified file with additional content, aka "WinVerifyTrust Signature Validation Vulnerability."
The vulnerability is being actively exploited; treat it as a priority. The available sources name no fixed version. Check the vendor guidance in the references below. Immediate actions, mitigation and detection rules are in the runbook below.
- Affected
- Microsoft Windows Server 2008
eq r2..r2
- Microsoft Windows Server 2008
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Metrics
7.8
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
7.8
CVSS v3
Severity High on the scale from 0 to 10.
Source: CVE.org
87.7 %
EPSS score
High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
Source: FIRST EPSS, percentile 99.76
Show all metrics
- Severity
- Critical
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 218.62 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- actively exploited
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 7.8 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 7.8
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 87.7 %
- High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 99.76
- Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- Actively exploited
- Published
In CISA KEV since
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- CISA assessment (SSVC)
- Exploitation: active · not automatable · Technical impact: total
- Source: CISA Vulnrichment, as of 4 February 2025
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-20
Response and mitigation
Why act now?
Prioritisation rationale
This flaw breaks the Authenticode trust model: attackers append content to a legitimately signed installer or binary, and Windows still reports it as validly signed. That makes it a good fit for drive-by downloads, trojanised software packages and phishing with apparently trustworthy vendor files. Exploitation requires local execution and user interaction but no prior authentication, and a successful attack fully compromises confidentiality, integrity and availability. Exploitation likelihood is very high, and CISA has no known ransomware use on record. For modern, patched estates this is a low priority. For KRITIS and OT operators still running XP, 2003, 2008 or Windows 7 systems, treat it as high priority, especially where signature-based allowlisting is the main control.
Runbook step 1
Immediate response (0-24 h)
- Inventory legacy hosts: Identify every host running Windows XP SP2/SP3, Server 2003 SP2, Vista SP2, Server 2008 SP2/R2/R2 SP1 or Windows 7 Gold/SP1 via CMDB, EDR or AD, e.g.
Get-ADComputer -Filter * -Properties OperatingSystem | ? OperatingSystem -match "XP|2003|Vista|2008|Windows 7". All of these versions are end-of-life. - Apply the vendor update: A patch is available from Microsoft — look up the exact version and KB ID in the vendor advisory. Verify deployment with
Get-HotFixor SCCM compliance reporting, and treat any unpatched host as exposed. - Isolate hosts that cannot be patched: Move OT/HMI, lab and line-of-business machines that cannot be updated into an isolated VLAN immediately. Block internet access, mail clients and browsing there, and route file transfers through a vetted data diode or sheep-dip station.
- Review signature-based allow rules: On affected hosts, temporarily replace allowlisting rules (AppLocker, SRP, third-party solutions) that trust a binary purely because of a valid Authenticode signature or publisher with hash-based rules.
- Block executable downloads: Stop executable downloads (
.exe,.dll,.msi,.scr) from the internet and from mail attachments for legacy segments at the proxy and mail gateway.
- Inventory legacy hosts: Identify every host running Windows XP SP2/SP3, Server 2003 SP2, Vista SP2, Server 2008 SP2/R2/R2 SP1 or Windows 7 Gold/SP1 via CMDB, EDR or AD, e.g.
Runbook step 2
Mitigation layers
- Configuration hardening (WinVerifyTrust): Enable strict Authenticode padding validation by setting
EnableCertPaddingCheck(REG_SZ, value1) underHKLM\Software\Microsoft\Cryptography\Wintrust\Config. On 64-bit systems, also set it underHKLM\Software\Wow6432Node\Microsoft\Cryptography\Wintrust\Config. Deploy via GPO, but test installers first, as some legitimate setups will then fail signature checks. - Network layer: Flag or block signed PE files that carry appended data beyond the certificate table (overlay) at the proxy or IPS. Apply default-deny egress for legacy VLANs and allow only required flows, such as WSUS or the specific application server.
- Endpoint hardening: Deny execution from user-writable paths (
%TEMP%,%APPDATA%,Downloads, removable media) via AppLocker or SRP path rules. Disable AutoRun for removable media. - IAM / least privilege: Remove local admin rights on affected hosts, since code runs in the user's context. Enforce LAPS or otherwise unique local admin passwords to limit lateral movement.
- Lifecycle governance: Record a documented risk acceptance for every legacy system that cannot be migrated, listing its compensating controls and a migration date. This is required evidence under NIS2 Art. 21 and ISO 27001 A.8.8.
- Configuration hardening (WinVerifyTrust): Enable strict Authenticode padding validation by setting
Runbook step 3
Detection rules
- Sysmon EID 1 / EID 7: Look for process creation or image loads with
Signed=trueand a trusted publisher whose hash does not match the known vendor build. A Sigma shape for this isImage|endswith: '.exe' AND Signature: 'Microsoft*' AND NOT Hashes in (known_good). Prioritise executions from\Downloads\,\Temp\or\Content.Outlook\. - EDR process ancestry: Watch for the chain
outlook.exe/iexplore.exe/winword.exe→ signed*.exein a user path →cmd.exe/powershell.exe/rundll32.exe. KQL:DeviceProcessEvents | where InitiatingProcessFolderPath has_any ("\\Downloads\\","\\Temp\\") and FileName in~ ("cmd.exe","powershell.exe","rundll32.exe"). - File analysis (YARA): Detect signed PEs with data trailing the security directory using
pe.number_of_signatures > 0 and filesize > pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_SECURITY].virtual_address + pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_SECURITY].size. Run it against proxy quarantine, the mail sandbox and file shares. - Windows Security 4688 / AppLocker 8002–8004: Alert on signed binaries executing on legacy hosts outside maintenance windows. Also alert on bursts of AppLocker blocks on those hosts.
- Network telemetry (Zeek
files.log): Trackmime_type == "application/x-dosexec"downloads to legacy-segment IPs. Compare file hashes against vendor references and threat intel.
- Sysmon EID 1 / EID 7: Look for process creation or image loads with
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
The Authenticode Signature Verification function in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, Windows 7 Gold and SP1, and Windows 8 Consumer Preview does not properly validate the digest of a signed portable executable (PE) file, which allows user-assisted remote attackers to execute arbitrary code via a modified file with additional content, aka "WinVerifyTrust Signature Validation Vulnerability."
Source: NVD (NIST), cvelistv5, CISA KEV Catalog, CVE.org (MITRE)
Vendors and products
Affected operating systems
| Windows | microsoft | windows_7 | — |
| Windows | microsoft | windows_server_2003 | — |
| Windows | microsoft | windows_server_2008 | r2 |
| Windows | microsoft | windows_server_2008 | — |
| Windows | microsoft | windows_vista | — |
| Windows | microsoft | windows_xp | — |
Weakness classes (CWE)
CWE-20Improper Input Validation
Class
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
Entry at MITRE CWE-20
Public exploit references
Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.
| CISA KEV Catalog | CISA Known Exploited Vulnerability (opens in a new tab)cisa.gov | actively exploited |
References & sources
- securitytracker.com1026906Vulnerability database, x_refsource_SECTRACK, Broken link, Third-party advisory, Vulnerability database
- osvdb.org81135Vulnerability database, x_refsource_OSVDB, Broken link
- us-cert.govTA12-101AThird-party advisory, x_refsource_CERT, Third-party advisory, US government resource
- secunia.com48581Third-party advisory, x_refsource_SECUNIA, Broken link
- docs.microsoft.comMS12-024Vendor advisory, x_refsource_MS, Patch, Vendor advisory
- oval.cisecurity.orgoval:org.mitre.oval:def:15594Vulnerability database, signature, x_refsource_OVAL, Broken link
- cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2012-0151government-resource, US government resource
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<a href="https://intel.neosec.eu/en/cve/CVE-2012-0151"><img src="https://intel.neosec.eu/badge/cve/CVE-2012-0151.svg?lang=en" alt="CVE-2012-0151 – NEOSEC Intel" height="20"></a>