2020-10 Security Bulletin: Junos OS: MX Series: MS-MPC/MIC might crash when processing malformed IPv6 packet in NAT64 configuration. (CVE-2020-1680)

Product Affected:

This issue affects Junos OS 15.1, 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. Affected platforms: MX Series.

Problem:

On Juniper Networks MX Series with MS-MIC or MS-MPC card configured with NAT64 configuration, receipt of a malformed IPv6 packet may crash the MS-PIC component on MS-MIC or MS-MPC.

This issue occurs when a multiservice card is translating the malformed IPv6 packet to IPv4 packet.

An unauthenticated attacker can continuously send crafted IPv6 packets through the device causing repetitive MS-PIC process crashes, resulting in an extended Denial of Service condition.

This issue affects Juniper Networks Junos OS on MX Series:

15.1 versions prior to 15.1R7-S7;
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-S6;
17.4 versions prior to 17.4R2-S11, 17.4R3;
18.1 versions prior to 18.1R3-S11;
18.2 versions prior to 18.2R3-S6;
18.2X75 versions prior to 18.2X75-D41, 18.2X75-D430, 18.2X75-D53, 18.2X75-D65;
18.3 versions prior to 18.3R2-S4, 18.3R3;
18.4 versions prior to 18.4R2-S5, 18.4R3;
19.1 versions prior to 19.1R2;
19.2 versions prior to 19.2R1-S5, 19.2R2;
19.3 versions prior to 19.3R2.

The example of the config stanza affected by this issue:

[services nat rule <rule_name> term <term_name> then translated translation-type stateful-nat64]

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

This issue was seen during production usage.

This issue has been assigned CVE-2020-1680.

Solution:

The following software releases have been updated to resolve this specific issue: Junos OS 15.1R7-S7, 15.1X53-D593, 16.1R7-S8, 17.2R3-S4, 17.3R3-S6, 17.4R2-S11, 17.4R3, 18.1R3-S11, 18.2R3-S6, 18.2X75-D41, 18.2X75-D430, 18.2X75-D53, 18.2X75-D65, 18.3R2-S4, 18.3R3, 18.4R2-S5, 18.4R3, 19.1R2, 19.2R1-S5, 19.2R2, 19.3R2, 19.4R1, and all subsequent releases.

This issue is being tracked as 1441517.

Workaround:

There are no viable workarounds for this issue.

Implementation:

Software releases or updates are available for download at https://www.juniper.net/support/downloads/.

Modification History:

2020-10-14: Initial Publication.

CVSS Score:

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

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