CVE-2019-19521: Critical severity openbsd vulnerability

Published Dec 4, 2019
·
Updated

libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/authsubr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).

Affected Software

1 affected component
OpenBSD OpenBSD=6.6

Event History

Dec 4, 2019
CVE Published
via MITRE·11:33 PM
Data Sourced
via MITRE·11:33 PM
Description

Frequently Asked Questions

1

What is CVE-2019-19521?

CVE-2019-19521 is a vulnerability in the libc library in OpenBSD 6.6 that allows authentication bypass via the -schallenge username.

2

How severe is CVE-2019-19521?

CVE-2019-19521 has a severity rating of 9.8, which is considered critical.

3

Which software version is affected by CVE-2019-19521?

OpenBSD 6.6 is the affected version of the software.

4

How can the authentication bypass be exploited?

The authentication bypass can be exploited by using the -schallenge username in services like smtpd, ldapd, or radiusd.

5

Are there any references for CVE-2019-19521?

References for CVE-2019-19521 can be found at the following links: http://packetstormsecurity.com/files/155572/Qualys-Security-Advisory-OpenBSD-Authentication-Bypass-Privilege-Escalation.html, http://seclists.org/fulldisclosure/2019/Dec/14, http://www.openwall.com/lists/oss-security/2019/12/04/5

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