CVE-2011-2666

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2011-07-06 · updated 2026-06-16
Weakness: CWE-16

Description

The default configuration of the SIP channel driver in Asterisk Open Source 1.4.x through 1.4.41.2 and 1.6.2.x through 1.6.2.18.2 does not enable the alwaysauthreject option, which allows remote attackers to enumerate account names by making a series of invalid SIP requests and observing the differences in the responses for different usernames, a different vulnerability than CVE-2011-2536.

Affected products

Digium Asterisk: 1.6.2.0, 1.6.2.0-rc2, 1.6.2.0-rc3, 1.6.2.0-rc4, 1.6.2.0-rc5, 1.6.2.0-rc6 (+152)

References

http://downloads.asterisk.org/pub/security/AST-2011-011.html
https://exchange.xforce.ibmcloud.com/vulnerabilities/68472
http://downloads.asterisk.org/pub/security/AST-2011-011.html
https://exchange.xforce.ibmcloud.com/vulnerabilities/68472

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