CVE-2026-46334: OpenSIPS: Denial of Service in SDP bandwidth parsing via QoS SDP cloning
OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Versions prior to 3.6.6 and 4.0.0-rc1 contain a denial of service vulnerability in the SDP bandwidth-line parsing logic. A SIP request with Content-Type: application/sdp and a malformed session-level SDP bandwidth line missing the required colon delimiter can corrupt parsed SDP bandwidth metadata. When a route or module subsequently clones the corrupted SDP state, as occurs with dialog and QoS processing, the OpenSIPS worker process crashes. An unauthenticated remote attacker can therefore trigger a crash in any configuration whose routing script parses attacker-controlled SDP and applies dialog/QoS processing. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
OpenSIPSto a version that resolves this vulnerability.Fixed in 3.6.6 - Upgrade
Upgrade
OpenSIPSto a version that resolves this vulnerability.Fixed in 4.0.0-rc1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-46334?
CVE-2026-46334 has a risk rating of 45, indicating potential severity.
How do I fix CVE-2026-46334?
To resolve CVE-2026-46334, upgrade your OpenSIPS version to 3.6.6 or later, or 4.0.0-rc1.
What type of vulnerability is CVE-2026-46334?
CVE-2026-46334 is a denial of service vulnerability linked to SDP bandwidth parsing.
Which versions of OpenSIPS are affected by CVE-2026-46334?
OpenSIPS versions prior to 3.6.6 and 4.0.0-rc1 are impacted by CVE-2026-46334.
What causes the CVE-2026-46334 vulnerability?
The vulnerability is caused by a null pointer dereference resulting from improper input validation in SDP bandwidth-line parsing.