OpenBSD 2.9/3.0/3.1 File Descriptor Table privileges management

Summaryinfo

A vulnerability was found in OpenBSD 2.9/3.0/3.1 and classified as problematic. The impacted element is an unknown function of the component File Descriptor Table Handler. Executing a manipulation can lead to privileges management. This vulnerability is tracked as CVE-2002-0766. Moreover, an exploit is present.

Detailsinfo

A vulnerability has been found in OpenBSD 2.9/3.0/3.1 (Operating System) and classified as critical. This vulnerability affects an unknown code of the component File Descriptor Table Handler. The manipulation with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

OpenBSD 2.9 through 3.1 allows local users to cause a denial of service (resource exhaustion) and gain root privileges by filling the kernel s file descriptor table and closing file descriptors 0, 1, or 2 before executing a privileged process, which is not properly handled when OpenBSD fails to open an alternate descriptor.

The bug was discovered 05/09/2002. The weakness was disclosed 05/10/2002 by Fozzy as confirmed advisory (CERT.org). The advisory is shared for download at kb.cert.org. This vulnerability was named CVE-2002-0766. The exploitation appears to be easy. The attack needs to be approached locally. No form of authentication is required for a successful exploitation. Technical details are unknown but an exploit is available. The MITRE ATT&CK project declares the attack technique as T1068.

An exploit has been developed in ANSI C and been published even before and not after the advisory. It is possible to download the exploit at dmpfrance.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $5k-$25k.

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

The vulnerability is also documented in the databases at X-Force (9048), SecurityFocus (BID 4708†) and OSVDB (5114†). The entry VDB-82001 is pretty similar. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Name

• OpenBSD

Version

• 2.9
• 3.0
• 3.1

License

• open-source

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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