CVE-2026-49841

FreeSWITCH: Pre-authentication heap buffer overflow in `mod_verto` HTTP POST body read

Published Jun 9, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
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 1.11.1, the mod_verto HTTP request handler allocates a fixed 2 MiB buffer for a POST application/x-www-form-urlencoded body but accepts Content-Length up to just under 10 MiB. The body-read loop is bounded by Content-Length rather than the buffer size, producing an attacker-controlled heap overflow of up to ~8 MiB -- before the HTTP basic-auth check runs. This issue has been patched in version 1.11.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Freeswitch
Freeswitch freeswitch
CPEs cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:*
Vendors & Products Freeswitch
Freeswitch freeswitch
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Signalwire
Signalwire freeswitch
Vendors & Products Signalwire
Signalwire freeswitch
Type Values Removed Values Added
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 1.11.1, the mod_verto HTTP request handler allocates a fixed 2 MiB buffer for a POST application/x-www-form-urlencoded body but accepts Content-Length up to just under 10 MiB. The body-read loop is bounded by Content-Length rather than the buffer size, producing an attacker-controlled heap overflow of up to ~8 MiB -- before the HTTP basic-auth check runs. This issue has been patched in version 1.11.1.
Title FreeSWITCH: Pre-authentication heap buffer overflow in `mod_verto` HTTP POST body read
Weaknesses CWE-122
CWE-131
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 11, 2026, 3:55 AM
Reserved
Jun 1, 2026, 6:50 PM
Status
Analyzed
Published
Jun 9, 2026, 5:17 PM
Modified
Jul 23, 2026, 8:10 AM