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CVE-1999-1591
Microsoft Internet Information Services (IIS) server 4.0 SP4, without certain hotfixes released for SP4, does not require authentication…
- 7.5HighCVSS base score
- 11.3%Exploitation in 30 daysEPSS · top 4.0% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Microsoft Internet Information Services (IIS) server 4.0 SP4, without certain hotfixes released for SP4, does not require authentication credentials under certain conditions, which allows remote attackers to bypass authentication requirements, as demonstrated by connecting via Microsoft Visual InterDev 6.0.
Timeline
ID reserved
By mitre
Published
- 17 years later
· 17 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 | 2.0 | High7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
- EPSS (exploitation in 30 days)
- 11.3% · top 4.0% of all CVEs (11 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
n/a
- affected n/a
References
References3
- 19990119 Re: IIS4.0 and Visual Interdev (opens in a new tab)mailing-listx_refsource_NTBUGTRAQx_transferred
- 190 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- 19990118 IIS4.0 and Visual Interdev (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)
- EUVD EUVD-1999-1572 (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-1999-1591)Record last updated .