CVE-2026-49840

Published: Giu 09, 2026 Last Modified: Giu 10, 2026
ExploitDB:
Other exploit source:
Google Dorks:
CRITICAL 9,1
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: high
Availability: high

Description

AI Translation Available

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, esl_recv_event() parses Content-Length with atol() and passes the result straight to malloc(len + 1) with no sign or magnitude check. A malicious or man-in-the-middle ESL peer can send a frame with a negative Content-Length to corrupt the heap of, or crash, any process linked against libesl, before the client has authenticated to that peer. This issue has been patched in version 1.11.1.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0006
Percentile
0,2th
Updated

EPSS Score Trend (Last 6 Days)

20

Improper Input Validation

Stable
Common Consequences
Security Scopes Affected:
Availability Confidentiality Integrity
Potential Impacts:
Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Read Memory Read Files Or Directories Modify Memory Execute Unauthorized Code Or Commands
Applicable Platforms
Technologies: AI/ML
View CWE Details
122

Heap-based Buffer Overflow

Draft
Common Consequences
Security Scopes Affected:
Availability Integrity Confidentiality Access Control Other
Potential Impacts:
Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Cpu) Dos: Resource Consumption (Memory) Execute Unauthorized Code Or Commands Bypass Protection Mechanism Modify Memory Other
Applicable Platforms
Languages: Memory-Unsafe, C, C++
View CWE Details
195

Signed to Unsigned Conversion Error

Draft
Common Consequences
Security Scopes Affected:
Integrity
Potential Impacts:
Unexpected State
Applicable Platforms
Languages: C, C++
View CWE Details
787

Out-of-bounds Write

Draft
Common Consequences
Security Scopes Affected:
Integrity Availability Other
Potential Impacts:
Modify Memory Execute Unauthorized Code Or Commands Dos: Crash, Exit, Or Restart Unexpected State
Applicable Platforms
Languages: Memory-Unsafe, C, C++, Assembly
Technologies: ICS/OT
View CWE Details
Application

Freeswitch by Freeswitch

Version Range Affected
To 1.11.1 (exclusive)
cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://github.com/signalwire/freeswitch/releases/tag/v1.11.1
https://github.com/signalwire/freeswitch/security/advisories/GHSA-g597-9fgg-ghg9