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CVE-2009-3727

Published: Nov 10, 2009Updated: Apr 23, 2026 Sources: CVE List NVDCWE-200
5.0MEDIUM
NVD MITRE
EPSS Score
4.2%
Top 10.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Asterisk Open Source 1.2.x before 1.2.35, 1.4.x before 1.4.26.3, 1.6.0.x before 1.6.0.17, and 1.6.1.x before 1.6.1.9; Business Edition A.x.x, B.x.x before B.2.5.12, C.2.x.x before C.2.4.5, and C.3.x.x before C.3.2.2; AsteriskNOW 1.5; and s800i 1.3.x before 1.3.0.5 generate different error messages depending on whether a SIP username is valid, which allows remote attackers to enumerate valid usernames via multiple crafted REGISTER messages with inconsistent usernames in the URI in the To header and the Digest in the Authorization header.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LAu:NC:PI:NA:N
Exploitability
AV:NAccess Vector
Network
AC:LAccess Complexity
Low
Au:NAuthentication
None
Impact
C:PConfidentiality
Partial
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-200

Affected Products

digium
commercial·USaka asterisk
asterisk
Communications
asterisknow
Communications
s800i
Communications
and 1 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

http://downloads.asterisk.org/pub/security/AST-2009-008.html
downloads.asterisk.org
http://osvdb.org/59697
osvdb.org
http://secunia.com/advisories/37265
secunia.com
and 9 more references View all →

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