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Fencer Intel
medium 6.0

CVE-2009-4445 json

Microsoft Internet Information Services (IIS), when used in conjunction with unspecified third-party upload applications, allows remote att…

published 16y ago modified 4mo ago also EUVD-2009-4412

cvss
6.0
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
12.8%
EPSS 12.8% chance of exploitation in 30 days, percentile 96%
public exploits
0
none known

Summary

Microsoft Internet Information Services (IIS), when used in conjunction with unspecified third-party upload applications, allows remote attackers to create empty files with arbitrary extensions via a filename containing an initial extension followed by a : (colon) and a safe extension, as demonstrated by an upload of a .asp:.jpg file that results in creation of an empty .asp file, related to support for the NTFS Alternate Data Streams (ADS) filename syntax. NOTE: it could be argued that this is a vulnerability in the third-party product, not IIS, because the third-party product should be applying its extension restrictions to the portion of the filename before the colon.

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Exploit prediction

12.76% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 2.0 6.0 AV:N/AC:M/Au:S/C:P/I:P/A:P

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.