CRITICAL
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."
Published Oct 6, 2004
9.8
CRITICALCVSS 3.0
EPSS 75.70%
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."
Affected products
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
9.8 CRITICAL NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact High
Integrity Impact High
Availability Impact High
7.5 HIGH NVD
AV:N/AC:L/Au:N/C:P/I:P/A:P
Access Vector Network
Access Complexity Low
Authentication None
Confidentiality Impact Partial
Integrity Impact Partial
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
75.70% 0.75702
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.75702
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (30 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 75.70% (0.75702) | 99.51th | v5 (v2026.06.15) |
| Sep 22, 2026 | 75.70% (0.75702) | 99.50th | v5 (v2026.06.15) |
| Sep 21, 2026 | 71.46% (0.71459) | 99.40th | v5 (v2026.06.15) |
| Sep 6, 2026 | 75.70% (0.75702) | 99.49th | v5 (v2026.06.15) |
| Sep 5, 2026 | 71.46% (0.71459) | 99.39th | v5 (v2026.06.15) |
| Aug 30, 2026 | 75.70% (0.75702) | 99.48th | v5 (v2026.06.15) |
| Aug 28, 2026 | 71.46% (0.71459) | 99.39th | v5 (v2026.06.15) |
| Aug 24, 2026 | 75.70% (0.75702) | 99.48th | v5 (v2026.06.15) |
| Aug 23, 2026 | 71.46% (0.71459) | 99.39th | v5 (v2026.06.15) |
| Aug 3, 2026 | 75.70% (0.75702) | 99.47th | v5 (v2026.06.15) |
| Jul 12, 2026 | 73.98% (0.73979) | 99.42th | v5 (v2026.06.15) |
| Jun 15, 2026 | 75.70% (0.75702) | 99.46th | v5 (v2026.06.15) |
| Jun 11, 2026 | 45.57% (0.45572) | 97.69th | v4 (v2025.03.14) |
| Dec 28, 2025 | 52.83% (0.52826) | 97.83th | v4 (v2025.03.14) |
| Dec 27, 2025 | 64.44% (0.64439) | 98.39th | v4 (v2025.03.14) |
| Nov 1, 2025 | 52.83% (0.52826) | 97.83th | v4 (v2025.03.14) |
| Oct 28, 2025 | 58.66% (0.58661) | 98.10th | v4 (v2025.03.14) |
| Oct 27, 2025 | 64.44% (0.64439) | 98.37th | v4 (v2025.03.14) |
| Oct 9, 2025 | 58.66% (0.58661) | 98.09th | v4 (v2025.03.14) |
| Oct 7, 2025 | 52.83% (0.52826) | 97.86th | v4 (v2025.03.14) |
| Oct 1, 2025 | 58.66% (0.58661) | 98.16th | v4 (v2025.03.14) |
| Mar 30, 2025 | 64.44% (0.64439) | 98.30th | v4 (v2025.03.14) |
| Mar 29, 2025 | 51.98% (0.51984) | 96.95th | v4 (v2025.03.14) |
| Mar 19, 2025 | 64.44% (0.64439) | 98.26th | v4 (v2025.03.14) |
| Mar 17, 2025 | 69.11% (0.69110) | 98.53th | v4 (v2025.03.14) |
| Dec 17, 2024 | 85.24% (0.85244) | 98.76th | v3 (v2023.03.01) |
| Sep 13, 2023 | 93.98% (0.93976) | 98.83th | v3 (v2023.03.01) |
| Mar 7, 2023 | 94.92% (0.94924) | 98.79th | v3 (v2023.03.01) |
| Mar 6, 2023 | 42.39% (0.42393) | 98.29th | v2 (v2022.01.01) |
| Feb 4, 2022 | 42.39% (0.42393) | 97.60th | v2 (v2022.01.01) |
Weaknesses (1)
References (9)
- http://archives.neohapsis.com/archives/ntbugtraq/2004-q3/0221.html mailing-listx_refsource_NTBUGTRAQExploitVendor Advisory
- http://sourceforge.net/mailarchive/forum.php?thread_id=5671607&forum_id=24754 x_refsource_MISCBroken Link
- http://www.kb.cert.org/vuls/id/283646 third-party-advisoryx_refsource_CERT-VNThird Party AdvisoryUS Government Resource
- http://www.securityfocus.com/bid/11342 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.us-cert.gov/cas/techalerts/TA05-039A.html third-party-advisoryx_refsource_CERTThird Party AdvisoryUS Government Resource
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2005/ms05-004 vendor-advisoryx_refsource_MS
- https://exchange.xforce.ibmcloud.com/vulnerabilities/17644 vdb-entryx_refsource_XFThird Party AdvisoryVDB Entry
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A3556 vdb-entrysignaturex_refsource_OVALThird Party Advisory
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A4987 vdb-entrysignaturex_refsource_OVALThird Party Advisory
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Oct 6, 2004
Updated Aug 8, 2024
Reserved Sep 8, 2004
Link CVE-2004-0847
CISA Vulnrichment
Updated n/a