#VU15707 Use of a broken or risky cryptographic algorithm in GnuTLS - CVE-2018-10844

Vulnerability identifier: #VU15707

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-10844

CWE-ID: CWE-327

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 gain access to potentially sensitive information.

The vulnerability exists due to usage of an insecure implementation of HMAC-SHA-256 algorithm vulnerable to a Lucky thirteen style attack. A remote attacker with ability to intercept traffic can recover encrypted data.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

GnuTLS: 0.0.3 - 3.6.2

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External links
https://www.securityfocus.com/bid/105138
https://access.redhat.com/errata/RHSA-2018:3050
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10844
https://eprint.iacr.org/2018/747
https://gitlab.com/gnutls/gnutls/merge_requests/657
https://lists.debian.org/debian-lts-announce/2018/10/msg00022.html

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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.