A vulnerability classified as critical was found in OpenBSD 6.6 (Operating System). Affected by this vulnerability is an unknown code block of the file gen/auth_subr.c of the component libc. The manipulation with the input value schallenge leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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

The weakness was presented 12/05/2019 (oss-sec). It is possible to read the advisory at openwall.com. This vulnerability is known as CVE-2019-19521. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/07/2024). Due to its background and reception, this vulnerability has a historic impact.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Type

• Operating System

Name

• OpenBSD

Version

• 6.6

License

• open-source

CPE 2.3info

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CPE 2.2info

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