Vulnerability Name:

CVE-2021-31376 (CCN-211289)

Assigned:2021-10-13
Published:2021-10-13
Updated:2021-10-25
Summary:An Improper Input Validation vulnerability in Packet Forwarding Engine manager (FXPC) process of Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) by sending specific DHCPv6 packets to the device and crashing the FXPC service. Continued receipt and processing of this specific packet will create a sustained Denial of Service (DoS) condition. This issue affects only the following platforms in ACX Series: ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096 devices. Other ACX platforms are not affected from this issue. This issue affects Juniper Networks Junos OS on ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096: 18.4 version 18.4R3-S7 and later versions prior to 18.4R3-S8. This issue does not affect: Juniper Networks Junos OS 18.4 versions prior to 18.4R3-S7 on ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096.
CVSS v3 Severity:7.5 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
6.5 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
7.5 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
6.5 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
7.8 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Complete
Vulnerability Type:CWE-20
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2021-31376

Source: XF
Type: UNKNOWN
juniper-cve202131376-dos(211289)

Source: CCN
Type: Juniper Networks Security Bulletin JSA11241
Junos OS: ACX Series: Packet Forwarding Engine manager (FXPC) process crashes when processing DHCPv6 packets (CVE-2021-31376)

Source: CONFIRM
Type: Vendor Advisory
https://kb.juniper.net/JSA11241

Vulnerable Configuration:Configuration 1:
  • cpe:/o:juniper:junos:18.4:r3-s7:*:*:*:*:*:*
  • AND
  • cpe:/h:juniper:acx1000:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx1100:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx2100:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx2200:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx4000:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx500:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx5048:-:*:*:*:*:*:*:*
  • OR cpe:/h:juniper:acx5096:-:*:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/o:juniper:junos:18.4:-:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    juniper junos 18.4 r3-s7
    juniper acx1000 -
    juniper acx1100 -
    juniper acx2100 -
    juniper acx2200 -
    juniper acx4000 -
    juniper acx500 -
    juniper acx5048 -
    juniper acx5096 -
    juniper junos 18.4 -