high
8.6
CWE
476
Advisory Published
Updated

CVE-2021-0251: Junos OS: MX Series with MS-PIC, MS-SPC3, MS-MIC or MS-MPC: The BRAS Subscriber Services service activation portal is vulnerable to a Denial of Service (DoS) via malformed HTTP packets

First published: Thu Apr 22 2021(Updated: )

A NULL Pointer Dereference vulnerability in the Captive Portal Content Delivery (CPCD) services daemon (cpcd) of Juniper Networks Junos OS on MX Series with MS-PIC, MS-SPC3, MS-MIC or MS-MPC allows an attacker to send malformed HTTP packets to the device thereby causing a Denial of Service (DoS), crashing the Multiservices PIC Management Daemon (mspmand) process thereby denying users the ability to login, while concurrently impacting other mspmand services and traffic through the device. Continued receipt and processing of these malformed packets will create a sustained Denial of Service (DoS) condition. While the Services PIC is restarting, all PIC services will be bypassed until the Services PIC completes its boot process. An attacker sending these malformed HTTP packets to the device who is not part of the Captive Portal experience is not able to exploit this issue. This issue is not applicable to MX RE-based CPCD platforms. This issue affects: Juniper Networks Junos OS on MX Series 17.3 version 17.3R1 and later versions prior to 17.4 versions 17.4R2-S9, 17.4R3-S2; 18.1 versions prior to 18.1R3-S9; 18.2 versions prior to 18.2R3-S3; 18.3 versions prior to 18.3R3-S1; 18.4 versions prior to 18.4R3; 19.1 versions prior to 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R3. This issue does not affect: Juniper Networks Junos OS versions prior to 17.3R1.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper JUNOS=17.3-r1
Juniper JUNOS=17.3-r1-s1
Juniper JUNOS=17.3-r1-s4
Juniper JUNOS=17.3-r2
Juniper JUNOS=17.3-r2-s1
Juniper JUNOS=17.3-r2-s2
Juniper JUNOS=17.3-r2-s3
Juniper JUNOS=17.3-r2-s4
Juniper JUNOS=17.3-r2-s5
Juniper JUNOS=17.3-r3
Juniper JUNOS=17.3-r3
Juniper JUNOS=17.3-r3-s1
Juniper JUNOS=17.3-r3-s10
Juniper JUNOS=17.3-r3-s2
Juniper JUNOS=17.3-r3-s3
Juniper JUNOS=17.3-r3-s4
Juniper JUNOS=17.3-r3-s5
Juniper JUNOS=17.3-r3-s6
Juniper JUNOS=17.3-r3-s7
Juniper JUNOS=17.3-r3-s8
Juniper JUNOS=17.3-r3-s9
Juniper JUNOS=17.4
Juniper JUNOS=17.4-r1
Juniper JUNOS=17.4-r1-s1
Juniper JUNOS=17.4-r1-s2
Juniper JUNOS=17.4-r1-s3
Juniper JUNOS=17.4-r1-s4
Juniper JUNOS=17.4-r1-s5
Juniper JUNOS=17.4-r1-s6
Juniper JUNOS=17.4-r1-s7
Juniper JUNOS=17.4-r2
Juniper JUNOS=17.4-r2-s1
Juniper JUNOS=17.4-r2-s2
Juniper JUNOS=17.4-r2-s3
Juniper JUNOS=17.4-r2-s4
Juniper JUNOS=17.4-r2-s5
Juniper JUNOS=17.4-r2-s6
Juniper JUNOS=17.4-r2-s7
Juniper JUNOS=17.4-r2-s8
Juniper JUNOS=17.4-r3
Juniper JUNOS=17.4-r3-s1
Juniper JUNOS=18.1
Juniper JUNOS=18.1-r1
Juniper JUNOS=18.1-r2
Juniper JUNOS=18.1-r2-s1
Juniper JUNOS=18.1-r2-s2
Juniper JUNOS=18.1-r2-s4
Juniper JUNOS=18.1-r3
Juniper JUNOS=18.1-r3-s1
Juniper JUNOS=18.1-r3-s2
Juniper JUNOS=18.1-r3-s3
Juniper JUNOS=18.1-r3-s4
Juniper JUNOS=18.1-r3-s5
Juniper JUNOS=18.1-r3-s6
Juniper JUNOS=18.1-r3-s7
Juniper JUNOS=18.1-r3-s8
Juniper JUNOS=18.2
Juniper JUNOS=18.2-r1
Juniper JUNOS=18.2-r1
Juniper JUNOS=18.2-r1-s2
Juniper JUNOS=18.2-r1-s3
Juniper JUNOS=18.2-r1-s4
Juniper JUNOS=18.2-r1-s5
Juniper JUNOS=18.2-r2
Juniper JUNOS=18.2-r2-s1
Juniper JUNOS=18.2-r2-s2
Juniper JUNOS=18.2-r2-s3
Juniper JUNOS=18.2-r2-s4
Juniper JUNOS=18.2-r2-s5
Juniper JUNOS=18.2-r2-s6
Juniper JUNOS=18.2-r2-s7
Juniper JUNOS=18.2-r3
Juniper JUNOS=18.2-r3-s1
Juniper JUNOS=18.2-r3-s2
Juniper JUNOS=18.3
Juniper JUNOS=18.3-r1
Juniper JUNOS=18.3-r1-s1
Juniper JUNOS=18.3-r1-s2
Juniper JUNOS=18.3-r1-s3
Juniper JUNOS=18.3-r1-s4
Juniper JUNOS=18.3-r1-s5
Juniper JUNOS=18.3-r1-s6
Juniper JUNOS=18.3-r2
Juniper JUNOS=18.3-r2-s1
Juniper JUNOS=18.3-r2-s2
Juniper JUNOS=18.3-r2-s3
Juniper JUNOS=18.3-r2-s4
Juniper JUNOS=18.3-r3
Juniper JUNOS=18.4
Juniper JUNOS=18.4-r1
Juniper JUNOS=18.4-r1-s1
Juniper JUNOS=18.4-r1-s2
Juniper JUNOS=18.4-r1-s3
Juniper JUNOS=18.4-r1-s4
Juniper JUNOS=18.4-r1-s5
Juniper JUNOS=18.4-r1-s6
Juniper JUNOS=18.4-r1-s7
Juniper JUNOS=18.4-r2
Juniper JUNOS=18.4-r2-s1
Juniper JUNOS=18.4-r2-s2
Juniper JUNOS=18.4-r2-s3
Juniper JUNOS=18.4-r2-s4
Juniper JUNOS=18.4-r2-s5
Juniper JUNOS=18.4-r2-s6
Juniper JUNOS=19.1
Juniper JUNOS=19.1-r1
Juniper JUNOS=19.1-r1-s1
Juniper JUNOS=19.1-r1-s2
Juniper JUNOS=19.1-r1-s3
Juniper JUNOS=19.1-r1-s4
Juniper JUNOS=19.1-r1-s5
Juniper JUNOS=19.1-r2
Juniper JUNOS=19.1-r2-s1
Juniper JUNOS=19.2
Juniper JUNOS=19.2-r1
Juniper JUNOS=19.2-r1-s1
Juniper JUNOS=19.2-r1-s2
Juniper JUNOS=19.2-r1-s3
Juniper JUNOS=19.2-r1-s4
Juniper JUNOS=19.2-r1-s5
Juniper JUNOS=19.3
Juniper JUNOS=19.3-r1
Juniper JUNOS=19.3-r1-s1
Juniper JUNOS=19.3-r2
Juniper JUNOS=19.3-r2-s1
Juniper JUNOS=19.3-r2-s2
Juniper JUNOS=19.3-r2-s3
Juniper JUNOS=19.3-r2-s4
Juniper JUNOS=19.3-r2-s5
Juniper Mx10
Juniper Mx10003
Juniper Mx10008
Juniper Mx10016
Juniper Mx104
Juniper Mx150
Juniper Mx2008
Juniper Mx2010
Juniper Mx2020
Juniper Mx204
Juniper Mx240
Juniper Mx40
Juniper Mx480
Juniper Mx5
Juniper Mx80
Juniper Mx960

Remedy

The following software releases have been updated to resolve this specific issue: 17.4R2-S9, 17.4R3-S2, 18.1R3-S9, 18.2R3-S3, 18.3R3-S1, 18.4R3, 19.1R2-S2, 19.1R3, 19.2R2, 19.3R3, 19.4R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0251?

    CVE-2021-0251 is categorized as a medium severity vulnerability that can lead to Denial of Service.

  • How do I fix CVE-2021-0251?

    To fix CVE-2021-0251, upgrade your Junos OS to a version that includes the necessary patches released by Juniper Networks.

  • What devices are affected by CVE-2021-0251?

    CVE-2021-0251 affects various Juniper MX Series devices running specific versions of Junos OS, including 17.3 and 18.1.

  • Is my device vulnerable to CVE-2021-0251?

    To determine if your device is vulnerable to CVE-2021-0251, check if it is on the list of affected versions of Junos OS.

  • What exploit is related to CVE-2021-0251?

    CVE-2021-0251 can be exploited by sending malformed HTTP packets to devices running the affected versions of Junos OS.

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