CVE-2026-116567 (GCVE-0-2026-116567)

Vulnerability from cvelistv5 – Published: 2026-11-05 19:23 – Updated: 2026-11-09 18:21
VLAI
Title
FreeSWITCH: Pre-authentication stack buffer overflow in mod_rtmp control-message handling
Summary
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 1.11.2, rtmp_handle_control() rendered an RTMP user-control message into a 200-byte stack buffer using an unbounded sprintf loop controlled by the wire message length. A body of roughly 70 bytes or more overflowed the stack before any RTMP login, because the handshake authenticates neither side. The flaw affects deployments that build and load mod_rtmp, which is disabled in the stock build and configuration but commonly exposes a listener on TCP port 1935 when enabled. One unauthenticated message can crash FreeSWITCH and end every active call; the constrained ASCII hex output has not yielded control-flow hijacking. This issue is fixed in version 1.11.2.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-09 18:19 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
signalwire freeswitch Affected: < 1.11.2
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