Vulnerability identifier: #VU18290

Vulnerability risk: Low

CVSSv3.1: 4.8 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2018-1000654

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
libtASN1
Universal components / Libraries / Libraries used by multiple products

Vendor: GNU

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input within the _asn1_expand_object_id(p_tree) function when parsing a specially crafted file with asn1Parser binary. An attacker can create a specially crafted file, pass it to the application and consume all available CPU resources on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

libtASN1: 4.0 - 4.13

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External links
http://www.securityfocus.com/bid/105151
http://gitlab.com/gnutls/libtasn1/issues/4
http://gitlab.com/gnutls/libtasn1/-/merge_requests/11

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.