2020-07 Security Bulletin: Junos OS: EX Series: RPD crash when executing specific "show ospf interface" commands from the CLI with OSPF authentication configured (CVE-2020-1643)

Product Affected:

This issue affects Junos OS 12.3X48, 14.1X53, 15.1, 15.1X49, 15.1X53, 16.1, 17.1, 17.2, 17.3, 17.4, 18.1, 18.2, 18.2X75, 18.3. Affected platforms: EX2300, EX3400.

Problem:

Execution of the "show ospf interface extensive" or "show ospf interface detail" CLI commands on a Juniper Networks device running Junos OS may cause the routing protocols process (RPD) to crash and restart if OSPF interface authentication is configured, leading to a Denial of Service (DoS). By continuously executing the same CLI commands, a local attacker can repeatedly crash the RPD process causing a sustained Denial of Service.

Note: Only systems utilizing ARM processors, found on the EX2300 and EX3400, are vulnerable to this issue. Systems shipped with other processor architectures are not vulnerable to this issue. The processor architecture can be displayed via the 'uname -a' command. For example:

ARM (vulnerable):
% uname -a | awk '{print $NF}' arm

PowerPC (not vulnerable):
% uname -a | awk '{print $NF}' powerpc

AMD (not vulnerable):
% uname -a | awk '{print $NF}'
amd64

Intel (not vulnerable):
% uname -a | awk '{print $NF}'
i386

This issue affects Juniper Networks Junos OS:

12.3X48 versions prior to 12.3X48-D100;
14.1X53 versions prior to 14.1X53-D140, 14.1X53-D54;
15.1 versions prior to 15.1R7-S7;
15.1X49 versions prior to 15.1X49-D210;
15.1X53 versions prior to 15.1X53-D593;
16.1 versions prior to 16.1R7-S8;
17.1 versions prior to 17.1R2-S12;
17.2 versions prior to 17.2R3-S4;
17.3 versions prior to 17.3R3-S8;
17.4 versions prior to 17.4R2-S2, 17.4R3;
18.1 versions prior to 18.1R3-S2;
18.2 versions prior to 18.2R2, 18.2R3;
18.2X75 versions prior to 18.2X75-D40;
18.3 versions prior to 18.3R1-S2, 18.3R2.

An example of a vulnerable configuration with OSPF authentication enabled is shown below:

area 0.0.0.0 {
interface ae0.0 {
authentication {
md5 0 key "$9$XyZzYxYzZyXyZzYxYzZy"; ## SECRET-DATA
}
}
}

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-2020-1643.

Solution:

The following software releases have been updated to resolve this specific issue: Junos OS 12.3X48-D100, 14.1X53-D140, 14.1X53-D54, 15.1R7-S7, 15.1X49-D210, 15.1X53-D593, 16.1R7-S8, 17.1R2-S12, 17.2R3-S4, 17.3R3-S8, 17.4R2-S2, 17.4R3, 18.1R3-S2, 18.2R2, 18.2X75-D40, 18.3R1-S2, 18.3R2, 18.4R1, and all subsequent releases.

This issue is being tracked as 1385014.

Workaround:

Limit access to the Junos CLI and shell to only trusted administrators.

Restrict access to "show ospf interface extensive" or "show ospf interface detail" via command authorization until an upgrade can be performed.

Implementation:

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

Modification History:

2020-07-08: Initial publication
2020-07-14: Clarified that only EX2300 and EX3400 are currently shipped with ARM processors

CVSS Score:

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

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