XXE in Freeswitch
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 <!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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (39.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.001
Affected products
- Freeswitch
- Signalwire Freeswitch — versions < 1.11.0
Weakness classification (CWE)
References
- github.com/signalwire/freeswitch/releases/tag/v1.11.0 (Product, Release Notes)
- github.com/signalwire/freeswitch/security/advisories/GHSA-5vjg-pv56-vg4c (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-45771?
- CVE-2026-45771 is a high-severity vulnerability in Freeswitch, classified under Improper Restriction of Recursive Entity References in DTDs (XML Entity Expansion). CVSS score: 7.5/10. Published 2026-06-09.
- How severe is CVE-2026-45771?
- High severity. CVSS v3 base score is 7.5 out of 10.