CVE-2016-9938
Summary
| CVE | CVE-2016-9938 |
|---|---|
| State | PUBLISHED |
| Assigner | mitre |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2016-12-12 21:59:01 UTC |
| Updated | 2026-05-06 22:30:45 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.0 5.3 MEDIUM from [email protected]
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS: 0.014190000 probability, percentile 0.807110000 (date 2026-05-11)
Problem Types: CWE-285 | n/a
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.0 | [email protected] | Primary | 5.3 | MEDIUM | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| 2.0 | [email protected] | Primary | 5 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
CVSS v3.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
LowAvailability
NoneCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS v2.0 Breakdown
Access Vector
NetworkAccess Complexity
LowAuthentication
NoneConfidentiality
NoneIntegrity
PartialAvailability
NoneAV:N/AC:L/Au:N/C:N/I:P/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Digium | Asterisk | 11.0.0 | All | All | All |
| Application | Digium | Asterisk | 11.0.0 | beta1 | All | All |
| Application | Digium | Asterisk | 11.0.0 | beta2 | All | All |
| Application | Digium | Asterisk | 11.0.0 | rc1 | All | All |
| Application | Digium | Asterisk | 11.0.0 | rc2 | All | All |
| Application | Digium | Asterisk | 11.0.1 | All | All | All |
| Application | Digium | Asterisk | 11.0.2 | All | All | All |
| Application | Digium | Asterisk | 11.1.0 | All | All | All |
| Application | Digium | Asterisk | 11.1.0 | rc1 | All | All |
| Application | Digium | Asterisk | 11.1.0 | rc3 | All | All |
| Application | Digium | Asterisk | 11.1.1 | All | All | All |
| Application | Digium | Asterisk | 11.1.2 | All | All | All |
| Application | Digium | Asterisk | 11.10.0 | All | All | All |
| Application | Digium | Asterisk | 11.10.1 | All | All | All |
| Application | Digium | Asterisk | 11.10.2 | All | All | All |
| Application | Digium | Asterisk | 11.11.0 | All | All | All |
| Application | Digium | Asterisk | 11.12.0 | All | All | All |
| Application | Digium | Asterisk | 11.12.1 | All | All | All |
| Application | Digium | Asterisk | 11.13.0 | All | All | All |
| Application | Digium | Asterisk | 11.13.1 | All | All | All |
| Application | Digium | Asterisk | 11.14.0 | All | All | All |
| Application | Digium | Asterisk | 11.14.1 | All | All | All |
| Application | Digium | Asterisk | 11.14.2 | All | All | All |
| Application | Digium | Asterisk | 11.15.0 | All | All | All |
| Application | Digium | Asterisk | 11.15.1 | All | All | All |
| Application | Digium | Asterisk | 11.16.0 | All | All | All |
| Application | Digium | Asterisk | 11.17.0 | All | All | All |
| Application | Digium | Asterisk | 11.17.1 | All | All | All |
| Application | Digium | Asterisk | 11.18.0 | All | All | All |
| Application | Digium | Asterisk | 11.19.0 | All | All | All |
| Application | Digium | Asterisk | 11.2.0 | All | All | All |
| Application | Digium | Asterisk | 11.2.0 | rc1 | All | All |
| Application | Digium | Asterisk | 11.2.0 | rc2 | All | All |
| Application | Digium | Asterisk | 11.2.1 | All | All | All |
| Application | Digium | Asterisk | 11.2.2 | All | All | All |
| Application | Digium | Asterisk | 11.20.0 | All | All | All |
| Application | Digium | Asterisk | 11.21.0 | All | All | All |
| Application | Digium | Asterisk | 11.21.1 | All | All | All |
| Application | Digium | Asterisk | 11.21.2 | All | All | All |
| Application | Digium | Asterisk | 11.22.0 | All | All | All |
| Application | Digium | Asterisk | 11.22.0 | rc1 | All | All |
| Application | Digium | Asterisk | 11.23.0 | All | All | All |
| Application | Digium | Asterisk | 11.23.0 | rc1 | All | All |
| Application | Digium | Asterisk | 11.23.1 | All | All | All |
| Application | Digium | Asterisk | 11.24.0 | All | All | All |
| Application | Digium | Asterisk | 11.24.1 | All | All | All |
| Application | Digium | Asterisk | 11.25.0 | All | All | All |
| Application | Digium | Asterisk | 11.3.0 | All | All | All |
| Application | Digium | Asterisk | 11.4.0 | All | All | All |
| Application | Digium | Asterisk | 11.5.0 | All | All | All |
| Application | Digium | Asterisk | 11.5.1 | All | All | All |
| Application | Digium | Asterisk | 11.6.0 | All | All | All |
| Application | Digium | Asterisk | 11.6.1 | All | All | All |
| Application | Digium | Asterisk | 11.7.0 | All | All | All |
| Application | Digium | Asterisk | 11.8.0 | All | All | All |
| Application | Digium | Asterisk | 11.8.1 | All | All | All |
| Application | Digium | Asterisk | 11.9.0 | All | All | All |
| Application | Digium | Asterisk | 13.0.0 | All | All | All |
| Application | Digium | Asterisk | 13.0.0 | beta1 | All | All |
| Application | Digium | Asterisk | 13.0.0 | beta2 | All | All |
| Application | Digium | Asterisk | 13.0.0 | beta3 | All | All |
| Application | Digium | Asterisk | 13.0.1 | All | All | All |
| Application | Digium | Asterisk | 13.0.2 | All | All | All |
| Application | Digium | Asterisk | 13.1.0 | All | All | All |
| Application | Digium | Asterisk | 13.1.1 | All | All | All |
| Application | Digium | Asterisk | 13.10.0 | All | All | All |
| Application | Digium | Asterisk | 13.10.0 | rc1 | All | All |
| Application | Digium | Asterisk | 13.11.0 | All | All | All |
| Application | Digium | Asterisk | 13.11.1 | All | All | All |
| Application | Digium | Asterisk | 13.11.2 | All | All | All |
| Application | Digium | Asterisk | 13.12.0 | All | All | All |
| Application | Digium | Asterisk | 13.12.1 | All | All | All |
| Application | Digium | Asterisk | 13.12.2 | All | All | All |
| Application | Digium | Asterisk | 13.13.0 | All | All | All |
| Application | Digium | Asterisk | 13.2.0 | All | All | All |
| Application | Digium | Asterisk | 13.2.1 | All | All | All |
| Application | Digium | Asterisk | 13.3.0 | All | All | All |
| Application | Digium | Asterisk | 13.3.1 | All | All | All |
| Application | Digium | Asterisk | 13.3.2 | All | All | All |
| Application | Digium | Asterisk | 13.4.0 | All | All | All |
| Application | Digium | Asterisk | 13.5.0 | All | All | All |
| Application | Digium | Asterisk | 13.6.0 | All | All | All |
| Application | Digium | Asterisk | 13.7.0 | All | All | All |
| Application | Digium | Asterisk | 13.7.1 | All | All | All |
| Application | Digium | Asterisk | 13.7.2 | All | All | All |
| Application | Digium | Asterisk | 13.8.0 | All | All | All |
| Application | Digium | Asterisk | 13.8.0 | rc1 | All | All |
| Application | Digium | Asterisk | 13.8.1 | All | All | All |
| Application | Digium | Asterisk | 13.8.2 | All | All | All |
| Application | Digium | Asterisk | 13.9.0 | All | All | All |
| Application | Digium | Asterisk | 13.9.1 | All | All | All |
| Application | Digium | Asterisk | 14.0.0 | All | All | All |
| Application | Digium | Asterisk | 14.0.0 | beta1 | All | All |
| Application | Digium | Asterisk | 14.0.0 | beta2 | All | All |
| Application | Digium | Asterisk | 14.0.0 | rc1 | All | All |
| Application | Digium | Asterisk | 14.0.0 | rc2 | All | All |
| Application | Digium | Asterisk | 14.0.1 | All | All | All |
| Application | Digium | Asterisk | 14.0.2 | All | All | All |
| Application | Digium | Asterisk | 14.1.0 | All | All | All |
| Application | Digium | Asterisk | 14.1.1 | All | All | All |
| Application | Digium | Asterisk | 14.1.2 | All | All | All |
| Application | Digium | Asterisk | 14.2.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.0.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.0.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.0.0 | rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.1.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.1.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.1.0 | rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.1.0 | rc3 | All | All |
| Application | Digium | Certified Asterisk | 11.2.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.2.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.2.0 | rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.3.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.3.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.3.0 | rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.4.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.4.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.4.0 | rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.4.0 | rc3 | All | All |
| Application | Digium | Certified Asterisk | 11.5.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.5.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.5.0 | rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert1 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert1 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert10 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert11 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert12 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert13 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert14 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert15 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert1_rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert1_rc2 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert2 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert2 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert3 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert3 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert4 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert5 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert6 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert7 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert8 | All | All |
| Application | Digium | Certified Asterisk | 11.6 | cert9 | All | All |
| Application | Digium | Certified Asterisk | 11.6.0 | All | All | All |
| Application | Digium | Certified Asterisk | 11.6.0 | - | All | All |
| Application | Digium | Certified Asterisk | 11.6.0 | rc1 | All | All |
| Application | Digium | Certified Asterisk | 11.6.0 | rc2 | All | All |
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| Asterisk Open Source and Certified Asterisk 'chan_sip' Driver Authentication Bypass Vulnerability | af854a3a-2127-422b-91ae-364da2661108 | www.securityfocus.com | Third Party Advisory, VDB Entry |
| Asterisk Lets Remote Users Bypass Proxy Authentication to Access the Target System - SecurityTracker | af854a3a-2127-422b-91ae-364da2661108 | www.securitytracker.com | |
| ASTERISK-2016-009 | af854a3a-2127-422b-91ae-364da2661108 | downloads.asterisk.org | Mitigation, Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.