Vulnerability Name:

CVE-2021-31353 (CCN-211294)

Assigned:2021-10-13
Published:2021-10-13
Updated:2021-10-25
Summary:An Improper Handling of Exceptional Conditions vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an attacker to inject a specific BGP update, causing the routing protocol daemon (RPD) to crash and restart, leading to a Denial of Service (DoS). Continued receipt and processing of the BGP update will create a sustained Denial of Service (DoS) condition. This issue affects very specific versions of Juniper Networks Junos OS: 19.3R3-S2; 19.4R3-S3; 20.2 versions 20.2R2-S3 and later, prior to 20.2R3-S2; 20.3 versions 20.3R2 and later, prior to 20.3R3; 20.4 versions 20.4R2 and later, prior to 20.4R3; 21.1 versions prior to 21.1R2. Juniper Networks Junos OS 20.1 is not affected by this issue. This issue also affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R2-S3-EVO, 20.4R3-EVO; 21.1-EVO versions prior to 21.1R2-EVO; 21.2-EVO versions prior to 21.2R2-EVO.
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-755
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2021-31353

Source: XF
Type: UNKNOWN
juniper-cve202131353-dos(211294)

Source: CCN
Type: Juniper Networks Security Bulletin JSA11218
Junos OS and Junos OS Evolved: RPD core upon receipt of specific BGP update (CVE-2021-31353)

Source: CONFIRM
Type: Exploit, Mitigation, Vendor Advisory
https://kb.juniper.net/JSA11218

Vulnerable Configuration:Configuration 1:
  • cpe:/o:juniper:junos:19.3:r3-s2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:19.4:r3-s3:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.2:r2-s3:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.2:r3:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.2:r3-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.3:r2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.3:r2-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.4:r2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.4:r2-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:21.1:r1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:21.1:r1-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:*:*:*:*:*:*:*:* (Version <= 20.3)
  • OR cpe:/o:juniper:junos_os_evolved:20.4:r1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:20.4:r1-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:20.4:r1-s2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:20.4:r2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:20.4:r2-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:20.4:r2-s2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:21.1:r1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:21.1:r1-s1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:21.2:r1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos_os_evolved:21.2:r1-s1:*:*:*:*:*:*

    • Configuration CCN 1:
  • cpe:/o:juniper:junos:19.3:r3-s2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.3:r2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.4:r2:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:21.1:r1:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:19.4:r3-s3:*:*:*:*:*:*
  • OR cpe:/o:juniper:junos:20.2:r2-s3:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    juniper junos 19.3 r3-s2
    juniper junos 19.4 r3-s3
    juniper junos 20.2 r2-s3
    juniper junos 20.2 r3
    juniper junos 20.2 r3-s1
    juniper junos 20.3 r2
    juniper junos 20.3 r2-s1
    juniper junos 20.4 r2
    juniper junos 20.4 r2-s1
    juniper junos 21.1 r1
    juniper junos 21.1 r1-s1
    juniper junos os evolved *
    juniper junos os evolved 20.4 r1
    juniper junos os evolved 20.4 r1-s1
    juniper junos os evolved 20.4 r1-s2
    juniper junos os evolved 20.4 r2
    juniper junos os evolved 20.4 r2-s1
    juniper junos os evolved 20.4 r2-s2
    juniper junos os evolved 21.1 r1
    juniper junos os evolved 21.1 r1-s1
    juniper junos os evolved 21.2 r1
    juniper junos os evolved 21.2 r1-s1
    juniper junos 19.3 r3-s2
    juniper junos 20.3 r2
    juniper junos 20.4 r2
    juniper junos 21.1 r1
    juniper junos 19.4 r3-s3
    juniper junos 20.2 r2-s3