CVE-2026-116780 · Runtime
NO FIX YET · SEE WHAT TO DO
FreeSWITCH before 1.11.2 reads past a heap buffer when expanding a variable with a positive offset, appending adjacent heap memory to the output. An attacker can read leaked channel variables, credentials or pointer bytes, mainly through configuration templates or authenticated Event Socket eval and expand commands.
first public Oct 28, 2026 · 1 source
Check it with your coding agent
It checks your repository and tells you if you’re affected, with the fix.
Systems running FreeSWITCH before 1.11.2 that use configuration templates slicing remote input, or that expose Event Socket eval or expand commands to authenticated users. The separate channel-variable expander used by ordinary dialplan slicing is unaffected, so deployments without those paths have lower exposure.
Not affected if fixed-version-1.11.2-or-later, no-event-socket-exposure
Who cares freeswitch, self-hosted, telecom
fs_cli -x version or the installed package version.${variable:offset} syntax.1.11.2FreeSWITCH 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, switch_event_expand_headers_check() advanced beyond its heap copy when a positive offset in ${variable:offset} exceeded the variable value's length. The following length calculation and copy appended adjacent heap memory to the expansion result, potentially exposing channel variables, credentials, allocator data, and pointer bytes. The flaw is reachable through configuration templates that slice remote input and through authenticated Event Socket eval or Event Socket expand commands; the separate channel-variable expander used by ordinary dialplan slicing is unaffected. The requester cannot choose adjacent memory and disclosure stops at a zero byte, but repeated expansion can influence the layout. This issue is fixed in version 1.11.2.
Are you affected?
Tell InfraStack what you run. It checks this one, and every next one, against your stack.
Ask from here. InfraStack checks the affected versions against your stack and answers in your inbox.
InfraStack checks the affected versions against your stack and answers in Slack, with the evidence and the fix.
NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.