Coturn up to 4.12.x IPv6 ioa_addr_is_loopback XOR-PEER-ADDRESS infinite loop

CVSS Meta Temp Score
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CTI Interest Score
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4.1$0-$5k0.56+

Summaryinfo

A vulnerability, which was classified as problematic, was found in Coturn up to 4.12.x. The impacted element is the function ioa_addr_is_loopback of the component IPv6 Handler. Such manipulation of the argument XOR-PEER-ADDRESS leads to infinite loop. This vulnerability is uniquely identified as CVE-2026-53450. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Coturn up to 4.12.x and classified as problematic. Affected by this issue is the function ioa_addr_is_loopback of the component IPv6 Handler. The manipulation of the argument XOR-PEER-ADDRESS with an unknown input leads to a infinite loop vulnerability. Using CWE to declare the problem leads to CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Impacted is confidentiality. CVE summarizes:

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, coturn rejects loopback peers by default unless allow-loopback-peers is enabled, but the default loopback guard can be bypassed by using the IPv4-mapped IPv6 peer address ::ffff:127.0.0.1 in a TURN XOR-PEER-ADDRESS attribute. ioa_addr_is_loopback checks for the literal IPv6 loopback shape before IPv4-mapped IPv6 handling, so good_peer_addr does not apply the default loopback rejection and an authenticated TURN client can expose services bound only to localhost on the coturn host through TURN relay traffic. This issue is fixed in version 4.13.0.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-53450 since 06/09/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 4.13.0 eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Infinite loop
CWE: CWE-835 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Coturn 4.13.0

Timelineinfo

06/09/2026 CVE reserved
07/10/2026 +31 days Advisory disclosed
07/10/2026 +0 days VulDB entry created
07/10/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-53450 (🔒)
GCVE (CVE): GCVE-0-2026-53450
GCVE (VulDB): GCVE-100-377582

Entryinfo

Created: 07/10/2026 20:45
Changes: 07/10/2026 20:45 (54)
Complete: 🔍
Cache ID: 216::103

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