Juniper Junos OS Vulnerability (JSA11246)

high Nessus Plugin ID 158896

Synopsis

The remote device is missing a vendor-supplied security patch.

Description

The version of Junos OS installed on the remote host is affected by a vulnerability as referenced in the JSA11246 advisory.

- In broadband environments, including but not limited to Enhanced Subscriber Management, (CHAP, PPP, DHCP, etc.), on Juniper Networks Junos OS devices where RADIUS servers are configured for managing subscriber access and a subscriber is logged in and then requests to logout, the subscriber may be forced into a 'Terminating' state by an attacker who is able to send spoofed messages appearing to originate from trusted RADIUS server(s) destined to the device in response to the subscriber's request. These spoofed messages cause the Junos OS General Authentication Service (authd) daemon to force the broadband subscriber into this 'Terminating' state which the subscriber will not recover from thereby causing a Denial of Service (DoS) to the endpoint device. Once in the 'Terminating'state, the endpoint subscriber will no longer be able to access the network. Restarting the authd daemon on the Junos OS device will temporarily clear the subscribers out of the 'Terminating' state. As long as the attacker continues to send these spoofed packets and subscribers request to be logged out, the subscribers will be returned to the 'Terminating' state thereby creating a persistent Denial of Service to the subscriber. An indicator of compromise may be seen by displaying the output of 'show subscribers summary'. The presence of subscribers in the 'Terminating' state may indicate the issue is occurring. (CVE-2021-31378)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Apply the relevant Junos software release referenced in Juniper advisory JSA11246

See Also

https://kb.juniper.net/JSA11246

Plugin Details

Severity: High

ID: 158896

File Name: juniper_jsa11246.nasl

Version: 1.3

Type: combined

Published: 3/14/2022

Updated: 4/27/2022

Configuration: Enable paranoid mode

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

Vector: AV:N/AC:M/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS Score Source: CVE-2021-31378

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:juniper:junos

Required KB Items: Host/Juniper/JUNOS/Version, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 10/13/2021

Vulnerability Publication Date: 10/13/2021

Reference Information

CVE: CVE-2021-31378

IAVA: 2021-A-0478-S

JSA: JSA11246