Ubuntu update for ARM mbed TLS

Published: 2020-02-08

Risk	High
Patch available	YES
Number of vulnerabilities	5
CVE-ID	CVE-2018-0498 CVE-2018-0497 CVE-2018-0488 CVE-2018-0487 CVE-2017-18187
CWE-ID	CWE-200 CWE-20 CWE-120 CWE-190
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	mbedtls (Ubuntu package) Operating systems & Components / Operating system package or component
Vendor	Canonical Ltd.

Security Bulletin

This security bulletin contains information about 5 vulnerabilities.

1) Information disclosure

EUVDB-ID: #VU14173

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-2018-0498

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

Exploit availability: No

Description

The vulnerability allows a remote attacker to obtain potentially sensitive information.

The vulnerability exists in ARM mbed TLS due to insufficient security restrictions imposed by the affected software when a cipher suite based on cipher block chaining (CBC) is used. A remote attacker who is able to observe and manipulate network packets can conduct a timing-based side-channel attack and partially recover the plaintext content.

Mitigation

Update the affected packages.

Ubuntu 16.04 LTS: libmbedcrypto0 - 2.2.1-2ubuntu0.3; libmbedtls10 - 2.2.1-2ubuntu0.3; libmbedx509-0 - 2.2.1-2ubuntu0.3

Vulnerable software versions

mbedtls (Ubuntu package): 2.2.1-2ubuntu0.1 - 2.2.1-2ubuntu0.2

CPE2.3

External links

https://usn.ubuntu.com/4267-1/

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) Information disclosure

EUVDB-ID: #VU14174

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-2018-0497

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

Exploit availability: No

Description

The vulnerability allows a remote attacker to obtain potentially sensitive information.

The vulnerability exists in ARM mbed TLS due to incomplete fix for CVE-2013-0169 and improper calculation of the secure hash algorithm-384 (SHA-384) when using a cipher suite based on cipher block chaining (CBC). A remote attacker who is able to observe and manipulate network packets can conduct a timing-based side-channel attack and partially recover the plaintext content.

Mitigation

Update the affected packages.

Ubuntu 16.04 LTS: libmbedcrypto0 - 2.2.1-2ubuntu0.3; libmbedtls10 - 2.2.1-2ubuntu0.3; libmbedx509-0 - 2.2.1-2ubuntu0.3

Vulnerable software versions

mbedtls (Ubuntu package): 2.2.1-2ubuntu0.1 - 2.2.1-2ubuntu0.2

CPE2.3

External links

https://usn.ubuntu.com/4267-1/

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) Remote code execution

EUVDB-ID: #VU10943

Risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2018-0488

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote unauthenticated attacker to execute arbitrary code on the target system.

The weakness exists due to improper processing of crafted packets when using the truncated HMAC extension and CBC. A remote attacker can send a specially crafted input and execute arbitrary code.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation

Update the affected packages.

Ubuntu 16.04 LTS: libmbedcrypto0 - 2.2.1-2ubuntu0.3; libmbedtls10 - 2.2.1-2ubuntu0.3; libmbedx509-0 - 2.2.1-2ubuntu0.3

Vulnerable software versions

mbedtls (Ubuntu package): 2.2.1-2ubuntu0.1 - 2.2.1-2ubuntu0.2

CPE2.3

External links

https://usn.ubuntu.com/4267-1/

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.

4) Buffer overflow

EUVDB-ID: #VU10955

Risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2018-0487

CWE-ID: CWE-120 - Buffer overflow

Exploit availability: No

Description

The vulnerability allows a remote unauthenticated attacker to execute arbitrary code on the target system.

The weakness exists due to improper validation of Rivest-Shamir-Adleman Probabilistic Signature Scheme (RSASSA-PSS) signatures. A remote attacker can send a specially crafted certificate chain, which the affected software can mishandle during RSASSA-PSS signature verification, trigger buffer overflow and execute arbitrary code.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation

Update the affected packages.

Ubuntu 16.04 LTS: libmbedcrypto0 - 2.2.1-2ubuntu0.3; libmbedtls10 - 2.2.1-2ubuntu0.3; libmbedx509-0 - 2.2.1-2ubuntu0.3

Vulnerable software versions

mbedtls (Ubuntu package): 2.2.1-2ubuntu0.1 - 2.2.1-2ubuntu0.2

CPE2.3

External links

https://usn.ubuntu.com/4267-1/

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.

5) Security restrictions bypass

EUVDB-ID: #VU11120

Risk: Low

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-18187

CWE-ID: CWE-190 - Integer overflow

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass security restrictions on the target system.

The weakness exists due to integer overflow in PSK identity parsing in the ssl_parse_client_psk_identity() function in library/ssl_srv.c. A remote attacker can trigger memory corruption and bypass bounds-check.

Mitigation

Update the affected packages.

Ubuntu 16.04 LTS: libmbedcrypto0 - 2.2.1-2ubuntu0.3; libmbedtls10 - 2.2.1-2ubuntu0.3; libmbedx509-0 - 2.2.1-2ubuntu0.3

Vulnerable software versions

mbedtls (Ubuntu package): 2.2.1-2ubuntu0.1 - 2.2.1-2ubuntu0.2

CPE2.3

External links

https://usn.ubuntu.com/4267-1/

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.