Lucky Thirteen Attack in GnuTLS implementation

1) Use of a broken or risky cryptographic algorithm

EUVDB-ID: #VU15707

Risk: Low

CVSSv3.1: 3.5 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-10844

CWE-ID: CWE-327 - Use of a Broken or Risky Cryptographic Algorithm

Exploit availability: No

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

External links

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

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.

2) Use of a broken or risky cryptographic algorithm

EUVDB-ID: #VU15708

Risk: Low

CVSSv3.1: 3.5 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-10845

CWE-ID: CWE-327 - Use of a Broken or Risky Cryptographic Algorithm

Exploit availability: No

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-384 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

External links

http://www.securityfocus.com/bid/105138
http://access.redhat.com/errata/RHSA-2018:3050
http://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10845
http://eprint.iacr.org/2018/747
http://gitlab.com/gnutls/gnutls/merge_requests/657
http://lists.debian.org/debian-lts-announce/2018/10/msg00022.html

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.

3) Cryptographic issues

EUVDB-ID: #VU15709

Risk: Low

CVSSv3.1: 3.5 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-10846

CWE-ID: CWE-310 - Cryptographic Issues

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a cache-based side channel in GnuTLS implementation that can lead to recovery of data in cross-VM attack setting. A remote attacker with ability to intercept traffic can recover encrypted data using a combination of "Just in Time" Prime+probe attack in combination with Lucky-13 attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

GnuTLS: 3.6.0 - 3.6.2

External links

http://www.securityfocus.com/bid/105138
http://access.redhat.com/errata/RHSA-2018:3050
http://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10846
http://eprint.iacr.org/2018/747
http://gitlab.com/gnutls/gnutls/merge_requests/657
http://lists.debian.org/debian-lts-announce/2018/10/msg00022.html

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.