Auth bypass in Microsoft Internet Information Services
CVE-2009-1535
The WebDAV extension in Microsoft Internet Information Services (IIS) 5.1 and 6.0 allows remote attackers to bypass URI-based protection mechanisms, and list folders or read, create, or modify files, via a %c0%af (Unicode / character) at an arbitrary position in the URI, as demonstrated by inserting %c0%af into a "/protected/" initial pathname component to bypass the password protection on the protected\ folder, aka "IIS 5.1 and 6.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1122.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v2 metric
CVSS v2 base score 7.5 (High). Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P. This CVE predates CVSS v3 and has no v3 score from NVD.
EPSS exploit prediction
EPSS: 0.981 (99.9th percentile), scored .
Very high probability of exploitation in the next 30 days — among the top 0.1% most-likely-to-be-exploited CVEs. 100th percentile — 99.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.981 · newest: 0.981 · change: 0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- oval.cisecurity.org/repository/search/definition/oval:org.mitre.oval:def:6029 (signature, Third Party Advisory, vdb-entry)
- docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-020 (vendor-advisory, Patch, Vendor Advisory)
- view.samurajdata.se/psview.php (Broken Link)
- isc.sans.org/diary.html (Third Party Advisory)
- archives.neohapsis.com/archives/fulldisclosure/2009-05/0135.html (mailing-list, Broken Link)
- archives.neohapsis.com/archives/fulldisclosure/2009-05/0139.html (mailing-list, Broken Link)
- blog.zoller.lu/2009/05/iis-6-webdac-auth-bypass-and-data.html (Third Party Advisory)
- www.us-cert.gov/cas/techalerts/TA09-160A.html (US Government Resource, Third Party Advisory, third-party-advisory)
- archives.neohapsis.com/archives/fulldisclosure/2009-05/att-0135/IIS_Advisory.pdf (Broken Link)
- archives.neohapsis.com/archives/fulldisclosure/2009-05/0144.html (mailing-list, Broken Link)
Frequently asked questions
- What is CVE-2009-1535?
- CVE-2009-1535 is a vulnerability in Microsoft Internet Information Services, classified under Improper Authentication. Published 2009-06-10.
- Is CVE-2009-1535 known to be exploited?
- 7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.