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CVE-2004-0847
The Microsoft .NET forms authentication capability for ASP.NET allows remote attackers to bypass authentication for .aspx files in…
Critical9.8EPSS 75.7%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
The Microsoft .NET forms authentication capability for ASP.NET allows remote attackers to bypass authentication for .aspx files in restricted directories via a request containing a (1) "\" (backslash) or (2) "%5C" (encoded backslash), aka "Path Validation Vulnerability."
Timeline
ID reserved
By mitre
- 28 days later
· 28 days later
Published
- 20 years later
· 20 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | Critical9.8 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 75.7% · top 0.5% of all CVEs (8 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
n/a
- affected n/a
References (9)
- MS05-004 (opens in a new tab)vendor-advisoryx_refsource_MSx_transferred
- http://sourceforge.net/mailarchive/forum.php?thread_id=5671607&forum_id=24754 (opens in a new tab)x_refsource_MISCx_transferred
- oval:org.mitre.oval:def:4987 (opens in a new tab)vdb-entrysignaturex_refsource_OVALx_transferred
- TA05-039A (opens in a new tab)third-party-advisoryx_refsource_CERTx_transferred
- windows-forms-security-bypass(17644) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- oval:org.mitre.oval:def:3556 (opens in a new tab)vdb-entrysignaturex_refsource_OVALx_transferred
- VU#283646 (opens in a new tab)third-party-advisoryx_refsource_CERT-VNx_transferred
- 11342 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- 20040914 Security bug in .NET Forms Authentication (opens in a new tab)mailing-listx_refsource_NTBUGTRAQx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2004-0847)Record last updated .