2020-07 Security Bulletin: Junos OS and Junos OS Evolved: OpenSSL Security Advisory [20 Dec 2019]

Product Affected:

This issue affects Junos OS 15.1, 15.1X49, 15.1X53, 16.1, 17.2, 17.3, 17.4, 18.1, 18.2, 18.2X75, 18.3, 18.4, 19.1, 19.2, 19.3, 19.4. This issue affects Junos OS Evolved 19.1, 19.2, 19.3, 19.4.

Problem:

The OpenSSL project has published a security advisory for a vulnerability resolved in the OpenSSL library on December 20, 2019.

This issue affects:

Juniper Networks Junos OS:

15.1 versions prior to 15.1R7-S7;
15.1X49 versions prior to 15.1X49-D230;
15.1X53 versions prior to 15.1X53-D593;
16.1 versions prior to 16.1R7-S8;
17.2 versions prior to 17.2R3-S4;
17.3 versions prior to 17.3R3-S8;
17.4 versions prior to 17.4R2-S10, 17.4R3-S1;
18.1 versions prior to 18.1R3-S10;
18.2 versions prior to 18.2R2-S7, 18.2R3-S4;
18.2X75 versions prior to 18.2X75-D60;
18.3 versions prior to 18.3R1-S7, 18.3R2-S4, 18.3R3-S2;
18.4 versions prior to 18.4R2-S4, 18.4R3-S1;
19.1 versions prior to 19.1R1-S5, 19.1R2-S1, 19.1R3;
19.2 versions prior to 19.2R1-S4, 19.2R2;
19.3 versions prior to 19.3R2-S2, 19.3R3;
19.4 versions prior to 19.4R1-S1, 19.4R2.

Juniper Networks Junos OS Evolved:

19.1 versions prior to 19.1R3-EVO
19.2 versions prior to 19.2R2-EVO;
19.3 versions prior to 19.3R3-EVO;
19.4 versions prior to 19.4R2-EVO.

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was discovered during an external security research.

The important security issue resolved is described below:

CVE	CVSS	Summary
CVE-2019-1551	5.3	There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t).

Solution:

The following software releases have been updated to resolve this specific issue:

Junos OS: 15.1R7-S7, 15.1X49-D230, 15.1X53-D593, 16.1R7-S8, 17.2R3-S4, 17.3R3-S8, 17.4R2-S10, 17.4R3-S1, 18.1R3-S10, 18.2R2-S7, 18.2R3-S4, 18.2X75-D60, 18.3R1-S7, 18.3R2-S4, 18.3R3-S2, 18.4R2-S4, 18.4R3-S1, 19.1R1-S5, 19.1R2-S1, 19.1R3, 19.2R1-S4, 19.2R2, 19.3R2-S2, 19.3R3, 19.4R1-S1, 19.4R2, 20.1R1, and all subsequent releases.

Junos OS Evolved: 19.1R3-EVO,19.2R2-EVO, 19.3R3-EVO, 19.4R2-EVO, 20.1R1-EVO, and all subsequent releases.

This issue is being tracked as 1479780 and 1485711.

Workaround:

Since SSL is used for remote network configuration and management applications such as J-Web and SSL Service for JUNOScript (XNM-SSL), viable workarounds for this issue in Junos may include:

Disabling J-Web
Disable SSL service for JUNOScript and only use Netconf, which makes use of SSH, to make configuration changes
Limit access to J-Web and XNM-SSL from only trusted networks

In addition to the recommendations listed above, it is good security practice to limit the exploitable attack surface of critical infrastructure networking equipment. Use access lists or firewall filters to limit access to the router via SSL only from trusted, administrative networks or hosts.

Implementation:

Software Releases, patches and updates are available at https://www.juniper.net/support/downloads/.

Modification History:

2020-07-08: Initial Publication

CVSS Score:

5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)

Severity Level:

Medium

Severity Assessment:

Information for how Juniper Networks uses CVSS can be found at KB 16446 "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

Knowledge Base