Authentication bypass in Sympa

Published: 2020-12-28
Risk Medium
Patch available YES
Number of vulnerabilities 1
CVE ID CVE-2020-29668
Exploitation vector Network
Public exploit N/A
Vulnerable software
Server applications / Mail servers


Security Advisory

This security advisory describes one medium risk vulnerability.

1) Improper Authentication

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2020-29668

CWE-ID: CWE-287 - Improper Authentication

Exploit availability: No


The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error in when processing authentication requests. A remote attacker can bypass authentication process and obtain full SOAP API access by sending any arbitrary string (except one from an expired cookie) as the cookie value to authenticateAndRun.


Install updates from vendor's website.

Vulnerable software versions

Sympa: 6.2.50, 6.2.52, 6.2.54, 6.2.56, 6.2.57, 6.2.57b.1, 6.2.57b.2, 6.2.58, 6.2.59b.1

CPE External links

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.