Home/CVE/chan_sip.c in the SIP channel driver in Asterisk Open Source 1.4.x before 1.4.41.2, 1.6.2.x before 1.6.2.18.2, and 1.8.x
CVE

CVE-2011-2536

chan_sip.c in the SIP channel driver in Asterisk Open Source 1.4.x before 1.4.41.2, 1.6.2.x before 1.6.2.18.2, and 1.8.x

chan_sip.c in the SIP channel driver in Asterisk Open Source 1.4.x before 1.4.41.2, 1.6.2.x before 1.6.2.18.2, and 1.8.x before 1.8.4.4, and Asterisk Business Edition C.3.x before C.3.7.3, disregards the alwaysauthreject option and generates different responses for invalid SIP requests depending on whether the user account exists, which allows remote attackers to enumerate account names via a series of requests.

MEDIUM · CVSS 5 EPSS 0.00187
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
▤

Affected Products & Versions

1
digium asteriskall versions
▣

Scoring & Timeline

5
MEDIUM · CVSS v2 (legacy) · cve@mitre.org
View on NVD
This CVE predates CVSS v3; the legacy v2 score is shown so triage still has a severity to work with.
v2 Vector
AV:N/AC:L/Au:N/C:P/I:N/A:N
Published to NVD06 Jul 2011 · 07:55 PM
🔗

References & Sources

3
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
http://downloads.asterisk.org/pub/security/AST-2011-011-1.8.diffPatch
http://downloads.asterisk.org/pub/security/AST-2011-011.htmlVendor Advisory
http://www.securitytracker.com/id?1025734
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