high
7.5
CWE
119
Advisory Published
Updated

CVE-2021-0227: Junos OS: SRX Series: Denial of Service in J-Web upon receipt of crafted HTTP packets

First published: Thu Apr 22 2021(Updated: )

An improper restriction of operations within the bounds of a memory buffer vulnerability in Juniper Networks Junos OS J-Web on SRX Series devices allows an attacker to cause Denial of Service (DoS) by sending certain crafted HTTP packets. Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. When this issue occurs, web-management, NTP daemon (ntpd) and Layer 2 Control Protocol process (L2CPD) daemons might crash. This issue affects Juniper Networks Junos OS on SRX Series: 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R3-S2; 19.2 versions prior to 19.2R1-S5, 19.2R3; 19.3 versions prior to 19.3R3; 19.4 versions prior to 19.4R2-S1, 19.4R3; 20.1 versions prior to 20.1R1-S2, 20.1R2;

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper JUNOS=17.3
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=17.4
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-s10
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-r2-s9
Juniper JUNOS=17.4-r3
Juniper JUNOS=17.4-r3-s1
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=18.2-r3-s3
Juniper JUNOS=18.2-r3-s4
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-r3
Juniper JUNOS=18.3-r3-s1
Juniper JUNOS=18.3-r3-s2
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-r3
Juniper JUNOS=18.4-r3-s1
Juniper JUNOS=18.4-r3-s2
Juniper JUNOS=18.4-r3-s3
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=19.1-r3
Juniper JUNOS=19.1-r3-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=19.3
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 JUNOS=19.4-r1
Juniper JUNOS=19.4-r1-s1
Juniper JUNOS=19.4-r1-s2
Juniper JUNOS=19.4-r2
Juniper JUNOS=20.1-r1
Juniper JUNOS=20.1-r1-s1
Juniper SRX100
Juniper SRX110
Juniper SRX1400
Juniper SRX1500
Juniper SRX210
Juniper SRX220
Juniper SRX240
Juniper SRX300
Juniper SRX320
Juniper SRX340
Juniper SRX3400
Juniper SRX345
Juniper SRX3600
Juniper SRX4100
Juniper SRX4200
Juniper SRX4600
Juniper SRX5400
Juniper SRX550
juniper srx5600
Juniper SRX5800
Juniper SRX650

Remedy

The following software releases have been updated to resolve this specific issue: 17.3R3-S9, 17.4R2-S11, 17.4R3-S2, 18.2R3-S5, 18.3R2-S4, 18.3R3-S3, 18.4R2-S5, 18.4R3-S4, 19.1R3-S2, 19.2R1-S5, 19.2R3, 19.3R3, 19.4R2-S1, 19.4R3, 20.1R1-S2, 20.1R2, 20.2R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0227?

    CVE-2021-0227 has a severity rating that indicates a Denial of Service (DoS) vulnerability.

  • How do I fix CVE-2021-0227?

    To fix CVE-2021-0227, you should apply the latest firmware updates from Juniper Networks for affected Junos OS versions.

  • Which devices are impacted by CVE-2021-0227?

    CVE-2021-0227 affects Juniper Networks SRX Series devices running vulnerable versions of Junos OS.

  • What type of attack does CVE-2021-0227 facilitate?

    CVE-2021-0227 facilitates a Denial of Service attack through crafted HTTP packets sent to affected devices.

  • Are there any workarounds for CVE-2021-0227?

    There are no documented workarounds for CVE-2021-0227; updating to a patched version is essential.

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