Coturn up to 4.9.x type conversion

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Coturn up to 4.9.x. The affected element is an unknown function. Performing a manipulation results in type conversion. This vulnerability is identified as CVE-2026-40613. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Coturn up to 4.9.x. This affects an unknown code. The manipulation with an unknown input leads to a type conversion vulnerability. CWE is classifying the issue as CWE-704. The product does not correctly convert an object, resource, or structure from one type to a different type. This is going to have an impact on availability. The summary by CVE is:

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.10.0, the STUN/TURN attribute parsing functions in coturn perform unsafe pointer casts from uint8_t * to uint16_t * without alignment checks. When processing a crafted STUN message with odd-aligned attribute boundaries, this results in misaligned memory reads at ns_turn_msg.c. On ARM64 architectures (AArch64) with strict alignment enforcement, this causes a SIGBUS signal that immediately kills the turnserver process. An unauthenticated remote attacker can crash any ARM64 coturn deployment by sending a single crafted UDP packet. This vulnerability is fixed in 4.10.0.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-40613 since 04/14/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 309094 (Linux Distros Unpatched Vulnerability : CVE-2026-40613), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.10.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (309094). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Type conversion
CWE: CWE-704
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 309094
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-40613

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Coturn 4.10.0

Timelineinfo

04/14/2026 CVE reserved
04/21/2026 +7 days Advisory disclosed
04/21/2026 +0 days VulDB entry created
04/22/2026 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-40613 (🔒)
GCVE (CVE): GCVE-0-2026-40613
GCVE (VulDB): GCVE-100-358551

Entryinfo

Created: 04/21/2026 20:56
Updated: 04/22/2026 17:52
Changes: 04/21/2026 20:56 (61), 04/22/2026 17:52 (2)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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