Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2020-26262— Loopback bypass in Coturn

Quick assessment

Affected
coturn coturn
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

CoTURN是一款TURN（VoIP媒体业务NAT穿越服务器和网关）和STUN（用户数据报协议简单穿越网络地址转换器）Server的开源实现。 Coturn 存在授权问题漏洞，攻击者可利用该漏洞绕过对数据的访问限制，以获取敏感信息。

CVSS 7.2 · High EPSS 1.32% · P68
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2020-26262

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Loopback bypass in Coturn
Source: CVE Program / CVE List V5
Vulnerability Description
Coturn is free open source implementation of TURN and STUN Server. Coturn before version 4.5.2 by default does not allow peers to connect and relay packets to loopback addresses in the range of `127.x.x.x`. However, it was observed that when sending a `CONNECT` request with the `XOR-PEER-ADDRESS` value of `0.0.0.0`, a successful response was received and subsequently, `CONNECTIONBIND` also received a successful response. Coturn then is able to relay packets to the loopback interface. Additionally, when coturn is listening on IPv6, which is default, the loopback interface can also be reached by making use of either `[::1]` or `[::]` as the peer address. By using the address `0.0.0.0` as the peer address, a malicious user will be able to relay packets to the loopback interface, unless `--denied-peer-ip=0.0.0.0` (or similar) has been specified. Since the default configuration implies that loopback peers are not allowed, coturn administrators may choose to not set the `denied-peer-ip` setting. The issue patched in version 4.5.2. As a workaround the addresses in the address block `0.0.0.0/8`, `[::1]` and `[::]` should be denied by default unless `--allow-loopback-peers` has been specified.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
未有动机的代理或中间人(混淆代理)
Source: CVE Program / CVE List V5
Vulnerability Title
CoTURN 授权问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
CoTURN是一款TURN（VoIP媒体业务NAT穿越服务器和网关）和STUN（用户数据报协议简单穿越网络地址转换器）Server的开源实现。 Coturn 存在授权问题漏洞，攻击者可利用该漏洞绕过对数据的访问限制，以获取敏感信息。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
coturn coturn < 4.5.2 -

II. Public POCs for CVE-2020-26262

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2020-26262

请登录查看更多情报信息。

Patches & Fixes for CVE-2020-26262 (1)

Vendor Advisories for CVE-2020-26262 (1)

Mailing List Discussions for CVE-2020-26262 (2)

Other References for CVE-2020-26262 (1)

IV. Related Vulnerabilities

Same product: coturn
Same vendor: coturn
Same weakness: CWE-441

V. Comments for CVE-2020-26262

No comments yet

Leave a comment