cbcvebase.
CVE-2016-9938
published 2016-12-12

CVE-2016-9938: An issue was discovered in Asterisk Open Source 11.x before 11.25.1, 13.x before 13.13.1, and 14.x before 14.2.1 and Certified Asterisk 11.x before 11.6-cert16…

PriorityP432medium5.3CVSS 3.0
AVNACLPRNUINSUCNILAN
EPSS
3.43%
87.4th percentile
An issue was discovered in Asterisk Open Source 11.x before 11.25.1, 13.x before 13.13.1, and 14.x before 14.2.1 and Certified Asterisk 11.x before 11.6-cert16 and 13.x before 13.8-cert4. The chan_sip channel driver has a liberal definition for whitespace when attempting to strip the content between a SIP header name and a colon character. Rather than following RFC 3261 and stripping only spaces and horizontal tabs, Asterisk treats any non-printable ASCII character as if it were whitespace. This means that headers such as Contact\x01: will be seen as a valid Contact header. This mostly does not pose a problem until Asterisk is placed in tandem with an authenticating SIP proxy. In such a case, a crafty combination of valid and invalid To headers can cause a proxy to allow an INVITE request into Asterisk without authentication since it believes the request is an in-dialog request. However, because of the bug described above, the request will look like an out-of-dialog request to Asterisk. Asterisk will then process the request as a new call. The result is that Asterisk can process calls from unvetted sources without any authentication. If you do not use a proxy for authentication, then this issue does not affect you. If your proxy is dialog-aware (meaning that the proxy keeps track of what dialogs are currently valid), then this issue does not affect you. If you use chan_pjsip instead of chan_sip, then this issue does not affect you.

Affected

93 ranges· showing 25
VendorProductVersion rangeFixed in
debianasterisk< asterisk 1:13.13.1~dfsg-1 (bullseye)asterisk 1:13.13.1~dfsg-1 (bullseye)
digiumasterisk
digiumasterisk
digiumasterisk
digiumasterisk
digiumasterisk
digiumasterisk
digiumasterisk
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digiumasterisk
digiumasterisk
digiumasterisk
digiumasterisk
digiumasterisk
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digiumasterisk
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digiumasterisk
digiumasterisk
digiumasterisk

CVSS provenance

nvdv3.05.3MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:P/A:N
osv5.3MEDIUM
vendor_debian5.3MEDIUM
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