PT-2020-5861 · Coturn+3 · Coturn+3

Alfredfarrugia

+1

·

Published

2020-10-01

·

Updated

2026-02-25

·

CVE-2020-26262

CVSS v2.0

8.5

High

VectorAV:N/AC:L/Au:S/C:C/I:C/A:N
Name of the Vulnerable Software and Affected Versions: Coturn versions prior to 4.5.2
Description: The issue is related to incorrect input validation in Coturn, a free open source implementation of TURN and STUN Server. By sending a CONNECT request with the XOR-PEER-ADDRESS value of 0.0.0.0, a malicious user can relay packets to the loopback interface, bypassing default access control protection. This can be achieved even when Coturn is listening on IPv6 by using either [::1] or [::] as the peer address. The estimated number of potentially affected devices worldwide is not specified. There is no information about real-world incidents where this issue was exploited.
Recommendations: For Coturn versions prior to 4.5.2, update to version 4.5.2 or later to resolve the issue. As a temporary workaround, consider denying the addresses in the address block 0.0.0.0/8, [::1], and [::] by default unless --allow-loopback-peers has been specified. Additionally, administrators can specify --denied-peer-ip=0.0.0.0 (or similar) to prevent malicious users from relaying packets to the loopback interface.

Exploit

Fix

Exposure of Resource to Wrong Sphere

Found an issue in the description? Have something to add? Feel free to write us 👾

Weakness Enumeration

Related Identifiers

ALT-PU-2021-2683
ALT-PU-2022-2460
BDU:2021-01906
BDU:2021-05112
CVE-2020-26262
DLA-2522-1
DSA-4829-1
GHSA-6G6J-R9RF-CM7P
MGASA-2021-0087
OPENSUSE-SU-2024:10696-1
USN-4690-1

Affected Products

Alt Linux
Coturn
Linuxmint
Ubuntu