CVEvulnerability

CVE-2016-9938

5.3 MEDIUM Published 2016-12-12 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2016-12-12
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.0 ([email protected])
5.3 MEDIUM — CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS 2.0 ([email protected])
5.0 MEDIUM — AV:N/AC:L/Au:N/C:N/I:P/A:N
Weaknesses
CWE-285

Description

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 configurations

• digium asterisk 11.0.0 • digium asterisk 11.0.1 • digium asterisk 11.0.2 • digium asterisk 11.1.0 • digium asterisk 11.1.1 • digium asterisk 11.1.2 • digium asterisk 11.2.0 • digium asterisk 11.2.1 • digium asterisk 11.2.2 • digium asterisk 11.3.0 • digium asterisk 11.4.0 • digium asterisk 11.5.0 • digium asterisk 11.5.1 • digium asterisk 11.6.0 • digium asterisk 11.6.1 • digium asterisk 11.7.0 • digium asterisk 11.8.0 • digium asterisk 11.8.1 • digium asterisk 11.9.0 • digium asterisk 11.10.0 • digium asterisk 11.10.1 • digium asterisk 11.10.2 • digium asterisk 11.11.0 • digium asterisk 11.12.0 • digium asterisk 11.12.1 • digium asterisk 11.13.0 • digium asterisk 11.13.1 • digium asterisk 11.14.0 • digium asterisk 11.14.1 • digium asterisk 11.14.2 • digium asterisk 11.15.0 • digium asterisk 11.15.1 • digium asterisk 11.16.0 • digium asterisk 11.17.0 • digium asterisk 11.17.1 • digium asterisk 11.18.0 • digium asterisk 11.19.0 • digium asterisk 11.20.0 • digium asterisk 11.21.0 • digium asterisk 11.21.1 • digium asterisk 11.21.2 • digium asterisk 11.22.0 • digium asterisk 11.23.0 • digium asterisk 11.23.1 • digium asterisk 11.24.0 • digium asterisk 11.24.1 • digium asterisk 11.25.0 • digium asterisk 13.0.0 • digium asterisk 13.0.1 • digium asterisk 13.0.2 • digium asterisk 13.1.0 • digium asterisk 13.1.1 • digium asterisk 13.2.0 • digium asterisk 13.2.1 • digium asterisk 13.3.0 • digium asterisk 13.3.1 • digium asterisk 13.3.2 • digium asterisk 13.4.0 • digium asterisk 13.5.0 • digium asterisk 13.6.0 … and 31 more

Related

Weakness · CWE (1)

  • CWE-285 Improper Authorization weakness

References