high
8.8
CWE
125
Advisory Published
Updated

CVE-2021-0277: Junos OS and Junos OS Evolved: LLDP Out-of-Bounds Read vulnerability in l2cpd

First published: Thu Jul 15 2021(Updated: )

An Out-of-bounds Read vulnerability in the processing of specially crafted LLDP frames by the Layer 2 Control Protocol Daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved may allow an attacker to cause a Denial of Service (DoS), or may lead to remote code execution (RCE). Continued receipt and processing of these frames, sent from the local broadcast domain, will repeatedly crash the l2cpd process and sustain the Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S18; 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S12; 17.4 versions prior to 17.4R2-S13, 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R2-S8, 18.4R3-S8; 19.1 versions prior to 19.1R3-S5; 19.2 versions prior to 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S3; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R2-S1, 20.3R3; 20.4 versions prior to 20.4R2. Juniper Networks Junos OS Evolved versions prior to 20.4R2-EVO.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper Junos=12.3
Juniper Junos=12.3-r1
Juniper Junos=12.3-r10
Juniper Junos=12.3-r10-s1
Juniper Junos=12.3-r10-s2
Juniper Junos=12.3-r11
Juniper Junos=12.3-r12
Juniper Junos=12.3-r12-s1
Juniper Junos=12.3-r12-s10
Juniper Junos=12.3-r12-s11
Juniper Junos=12.3-r12-s12
Juniper Junos=12.3-r12-s13
Juniper Junos=12.3-r12-s14
Juniper Junos=12.3-r12-s15
Juniper Junos=12.3-r12-s16
Juniper Junos=12.3-r12-s17
Juniper Junos=12.3-r12-s3
Juniper Junos=12.3-r12-s4
Juniper Junos=12.3-r12-s6
Juniper Junos=12.3-r12-s8
Juniper Junos=15.1
Juniper Junos=15.1-a1
Juniper Junos=15.1-f
Juniper Junos=15.1-f1
Juniper Junos=15.1-f2
Juniper Junos=15.1-f2-s1
Juniper Junos=15.1-f2-s2
Juniper Junos=15.1-f2-s3
Juniper Junos=15.1-f2-s4
Juniper Junos=15.1-f3
Juniper Junos=15.1-f4
Juniper Junos=15.1-f5
Juniper Junos=15.1-f5-s7
Juniper Junos=15.1-f6
Juniper Junos=15.1-f6-s1
Juniper Junos=15.1-f6-s10
Juniper Junos=15.1-f6-s12
Juniper Junos=15.1-f6-s2
Juniper Junos=15.1-f6-s3
Juniper Junos=15.1-f6-s4
Juniper Junos=15.1-f6-s5
Juniper Junos=15.1-f6-s6
Juniper Junos=15.1-f6-s7
Juniper Junos=15.1-f6-s8
Juniper Junos=15.1-f6-s9
Juniper Junos=15.1-f7
Juniper Junos=15.1-r
Juniper Junos=15.1-r1
Juniper Junos=15.1-r2
Juniper Junos=15.1-r3
Juniper Junos=15.1-r4
Juniper Junos=15.1-r4-s7
Juniper Junos=15.1-r4-s8
Juniper Junos=15.1-r4-s9
Juniper Junos=15.1-r5
Juniper Junos=15.1-r5-s1
Juniper Junos=15.1-r5-s3
Juniper Junos=15.1-r5-s5
Juniper Junos=15.1-r5-s6
Juniper Junos=15.1-r6
Juniper Junos=15.1-r6-s1
Juniper Junos=15.1-r6-s2
Juniper Junos=15.1-r6-s3
Juniper Junos=15.1-r6-s4
Juniper Junos=15.1-r6-s6
Juniper Junos=15.1-r7
Juniper Junos=15.1-r7-s1
Juniper Junos=15.1-r7-s2
Juniper Junos=15.1-r7-s3
Juniper Junos=15.1-r7-s4
Juniper Junos=15.1-r7-s5
Juniper Junos=15.1-r7-s6
Juniper Junos=15.1-r7-s7
Juniper Junos=15.1-r7-s8
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-s11
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-s10
Juniper Junos=17.4-r2-s11
Juniper Junos=17.4-r2-s12
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=17.4-r3-s2
Juniper Junos=17.4-r3-s3
Juniper Junos=17.4-r3-s4
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-s10
Juniper Junos=18.1-r3-s11
Juniper Junos=18.1-r3-s12
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=18.1-r3-s9
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=18.2-r3-s5
Juniper Junos=18.2-r3-s6
Juniper Junos=18.2-r3-s7
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=18.4-r2-s7
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=18.4-r3-s4
Juniper Junos=18.4-r3-s5
Juniper Junos=18.4-r3-s6
Juniper Junos=18.4-r3-s7
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-r1-s6
Juniper Junos=19.1-r2
Juniper Junos=19.1-r2-s1
Juniper Junos=19.1-r2-s2
Juniper Junos=19.1-r3
Juniper Junos=19.1-r3-s1
Juniper Junos=19.1-r3-s2
Juniper Junos=19.1-r3-s3
Juniper Junos=19.1-r3-s4
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=19.2-r1-s6
Juniper Junos=19.2-r2
Juniper Junos=19.2-r2-s1
Juniper Junos=19.2-r3
Juniper Junos=19.2-r3-s1
Juniper Junos=19.2-r3-s2
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=19.3-r3
Juniper Junos=19.3-r3-s1
Juniper Junos=19.4-r1
Juniper Junos=19.4-r1-s1
Juniper Junos=19.4-r1-s2
Juniper Junos=19.4-r1-s3
Juniper Junos=19.4-r2
Juniper Junos=19.4-r2-s1
Juniper Junos=19.4-r2-s2
Juniper Junos=19.4-r2-s3
Juniper Junos=19.4-r3
Juniper Junos=19.4-r3-s1
Juniper Junos=19.4-r3-s2
Juniper Junos=20.1-r1
Juniper Junos=20.1-r1-s1
Juniper Junos=20.1-r1-s2
Juniper Junos=20.1-r1-s3
Juniper Junos=20.1-r1-s4
Juniper Junos=20.1-r2
Juniper Junos=20.1-r2-s1
Juniper Junos=20.2-r1
Juniper Junos=20.2-r1-s1
Juniper Junos=20.2-r1-s2
Juniper Junos=20.2-r1-s3
Juniper Junos=20.2-r2
Juniper Junos=20.2-r2-s1
Juniper Junos=20.2-r2-s2
Juniper Junos=20.2-r2-s3
Juniper Junos=20.2-r3
Juniper Junos=20.3-r1
Juniper Junos=20.3-r1-s1
Juniper Junos=20.3-r2
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 12.3R12-S18, 15.1R7-S9, 17.3R3-S12, 17.4R2-S13, 17.4R3-S5, 18.1R3-S13, 18.2R3-S8, 18.3R3-S5, 18.4R2-S8, 18.4R3-S8, 19.1R3-S5, 19.3R2-S6, 19.3R3-S2, 19.4R1-S4, 19.4R2-S4, 19.4R3-S3, 20.1R2-S2, 20.1R3, 20.2R3-S1, 20.3R2-S1, 20.3R3, 20.4R2, 20.4R3, 21.1R1, 21.1R2, 21.2R1, and all subsequent releases. Junos OS Evolved 20.4R2-EVO, 21.1R1-EVO, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0277?

    CVE-2021-0277 is considered a critical vulnerability due to the potential for denial of service and remote code execution.

  • How do I fix CVE-2021-0277?

    To fix CVE-2021-0277, it's recommended to upgrade to the latest patched version of Junos OS provided by Juniper Networks.

  • What versions of Junos OS are affected by CVE-2021-0277?

    CVE-2021-0277 affects multiple versions of Junos OS, including versions 12.3, 15.1, 17.3, 17.4, and 18.1 through 20.4.

  • What type of attack does CVE-2021-0277 enable?

    CVE-2021-0277 enables attackers to conduct denial of service attacks or potentially execute remote code on affected devices.

  • Is there a workaround for CVE-2021-0277?

    There are no known workarounds for CVE-2021-0277, making the upgrade to a patched version the only effective solution.

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