#VU18106 Buffer overflow in GnuTLS - CVE-2019-3836

Vulnerability identifier: #VU18106

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-3836

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

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

Vendor: GnuTLS

Description

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

The vulnerability exists due to uninitialized pointer access when processing TLS1.3 asynchronous messages. A remote attacker can pass specially crafted asynchronous post-handshake message, trigger memory corruption and perform denial of service attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

GnuTLS: 3.6.4 - 3.6.6

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External links
https://www.gnutls.org/security-new.html#GNUTLS-SA-2019-03-27
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3836
https://gitlab.com/gnutls/gnutls/issues/704

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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.