Security features bypass in coTURN - CVE-2020-26262

Vulnerability identifier: #VU49937

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2020-26262

CWE-ID: CWE-254

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists in the way the Coturn handles CONNECT requests with XOR-PEER-ADDRESS set to "0.0.0.0". A remote attacker can send specially crafted request to the affected server and force Coturn relay on the loopback addresses, such as 127.x.x.x and ::1, which is disabled by default.

coTURN
Arch Linux
Fedora
Ubuntu
coturn (Debian package)
coturn (Alpine package)
coturn (Ubuntu package)
coturn

Install updates from vendor's website.

coTURN - update to 4.5.2
coturn (Debian package) - update to 4.5.1.1-1.1+deb10u2
coturn (Alpine package) - update to 4.5.2-r0
coturn (Ubuntu package) - addressed in versions 4.5.0.3-1ubuntu0.4, 4.5.0.7-1ubuntu2.18.04.3, 4.5.1.1-1.1ubuntu0.20.04.2, 4.5.1.3-1ubuntu0.1
coturn - addressed in versions 4.5.2-1.el7, 4.5.2-1.el8, 4.5.2-1.fc32, 4.5.2-1.fc33

• https://github.com/coturn/coturn/blob/57180ab60afcaeb13537e69ae8cb8aefd8f3f546/ChangeLog#L48
• https://github.com/coturn/coturn/commit/abfe1fd08d78baa0947d17dac0f7411c3d948e4d
• https://github.com/coturn/coturn/security/advisories/GHSA-6g6j-r9rf-cm7p
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/G54UIUFTEC6RLPOISMB6FUW7456SBZC4/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/M4CJOPAQT43MYAFU3UROGLEXN3Z6RS4H/

• Security restrictions bypass in Coturn
• Debian update for coturn
• Security features bypass in coturn (Alpine package)
• Arch Linux update for coturn
• Ubuntu update for coturn
• Fedora 33 update for coturn
• Fedora 32 update for coturn
• Fedora EPEL 8 update for coturn
• Fedora EPEL 7 update for coturn