CVE-2026-116783 FreeSWITCH mod_spandsp: out-of-bounds write parsing UDPTL error-recovery data
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-116783?
CVE-2026-116783 is a high-severity vulnerability in signalwire freeswitch, published on 5 Nov 2026.
Official 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 1.11.2, udptl_rx_packet() used a peer-controlled FEC entry count directly to fill five-entry FEC arrays in a mod_spandsp T.38 session. A larger count wrote sender-controlled error-recovery data beyond those arrays and persisted the oversized count for a later reconstruction pass. Any peer able to deliver UDPTL to an established T.38 fax session can reach the parser, including deployments using fax applications or a T.38 gateway. The memory corruption can crash FreeSWITCH and end every active call, although remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.
Which versions are affected by CVE-2026-116783?
It affects 1 product.
Products include Freeswitch.
How do I fix CVE-2026-116783?
No fix has been published for CVE-2026-116783 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-116783 being exploited?
There is no known exploitation of CVE-2026-116783 in the wild and no public exploit code.
Other vulnerabilities in signalwire freeswitch
- CVE-2026-116779 SignalWire FreeSwitch Code Injection
- CVE-2026-49841 FreeSWITCH: Pre-authentication heap buffer overflow in `mod_verto` HTTP POST body read
- CVE-2019-19492 FreeSWITCH 1.6.10 through 1.10.1 has a default password in event_socket.conf.xml.
- CVE-2026-116785 FreeSWITCH: Pre-authentication heap out-of-bounds write in mod_xml_rpc WebSocket frame length handling
- CVE-2026-116790 FreeSWITCH: Inbound ICE connectivity checks are accepted without verifying STUN MESSAGE-INTEGRITY
Sources
Also known as GHSA-mjp3-3cq2-hxj4.