Freeswitch Denial-of-Service in SIP PUBLISH Requests via XML Entity Expansion
CVE-2026-45771

7.5HIGH

Key Information:

Vendor

Signalwire

Status
Freeswitch
Vendor
CVE Published:
9 June 2026

What is CVE-2026-45771?

FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to version 1.11.0, FreeSWITCH's bundled XML parser expands nested declarations without a depth or count bound, so a small DTD can describe a body that expands exponentially ("billion laughs"). The PIDF body of a SIP PUBLISH is fed to this parser before any digest check, letting an unauthenticated network attacker force unbounded CPU and memory consumption with a single request. This issue has been patched in version 1.11.0.

Affected Version(s)

freeswitch < 1.11.0

References

https://github.com/signalwire/freeswitch/security/advisor...
x_refsource_CONFIRM
https://github.com/signalwire/freeswitch/releases/tag/v1....
x_refsource_MISC

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.