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TI-2026-36745 Aliases CVE-2026-49841

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

Priority MEDIUM 49CWE-122Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.

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 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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00394 33rd percentileScored 2026-11-07
Fix Fixed freeswitch (signalwire): 1.11.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
signalwirefreeswitchbefore 1.11.11.11.1Patch availableCNA
  • freeswitch Vendorsignalwire Affected before 1.11.1 Fixed in 1.11.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:*before 1.11.1Vulnerablefreeswitch
  • cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:* Versions before 1.11.1 Vulnerable ·freeswitch

Remediation

  • Fix · CNA freeswitch (signalwire) Fixed in 1.11.1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49841

References

Advisory 1

Other 1

  • TI-2023-08915 heap-over-flow in stun_parse_attribute in sofia-sip CVSS 3.1CRITICAL 9.8
  • TI-2022-13049 Heap-based Buffer Overflow and Out-of-bounds Write in Sofia-SIP CVSS 3.1CRITICAL 9.8
  • TI-2023-28097 FreeSWITCH susceptible to Denial of Service via DTLS Hello packets during call initiation CVSS 3.1HIGH 7.5
  • TI-2023-20909 Resource allocation without limits in signalwire freeswitch CVSS 3.1HIGH 7.5
  • TI-2023-20908 FreeSWITCH allows remote users to trigger out of bounds write by offering an ICE candidate with unknown component ID CVSS 3.1HIGH 7.5
  • TI-2023-15601 heap-over-flow and integer-overflow in sofia-sip CVSS 3.1HIGH 7.5
See all 44 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences