CWE
362
Advisory Published
Updated

CVE-2021-0247: Junos OS: PTX Series, QFX Series: Due to a race condition input loopback firewall filters applied to interfaces may not operate even when listed in the running configuration.

First published: Wed Apr 14 2021(Updated: )

A Race Condition (Concurrent Execution using Shared Resource with Improper Synchronization) vulnerability in the firewall process (dfwd) of Juniper Networks Junos OS allows an attacker to bypass the firewall rule sets applied to the input loopback filter on any interfaces of a device. This issue is detectable by reviewing the PFE firewall rules, as well as the firewall counters and seeing if they are incrementing or not. For example: show firewall Filter: __default_bpdu_filter__ Filter: FILTER-INET-01 Counters: Name Bytes Packets output-match-inet 0 0 <<<<<< missing firewall packet count This issue affects: Juniper Networks Junos OS 14.1X53 versions prior to 14.1X53-D53 on QFX Series; 14.1 versions 14.1R1 and later versions prior to 15.1 versions prior to 15.1R7-S6 on QFX Series, PTX Series; 15.1X53 versions prior to 15.1X53-D593 on QFX Series; 16.1 versions prior to 16.1R7-S7 on QFX Series, PTX Series; 16.2 versions prior to 16.2R2-S11, 16.2R3 on QFX Series, PTX Series; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2 on QFX Series, PTX Series; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3 on QFX Series, PTX Series; 17.3 versions prior to 17.3R2-S5, 17.3R3-S7 on QFX Series, PTX Series; 17.4 versions prior to 17.4R2-S9, 17.4R3 on QFX Series, PTX Series; 18.1 versions prior to 18.1R3-S9 on QFX Series, PTX Series; 18.2 versions prior to 18.2R2-S6, 18.2R3-S3 on QFX Series, PTX Series; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3-S1 on QFX Series, PTX Series; 18.4 versions prior to 18.4R1-S5, 18.4R2-S3, 18.4R2-S7, 18.4R3 on QFX Series, PTX Series; 19.1 versions prior to 19.1R1-S4, 19.1R2-S1, 19.1R3 on QFX Series, PTX Series; 19.2 versions prior to 19.2R1-S3, 19.2R2 on QFX Series, PTX Series.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Junos OS Evolved=14.1x53
Junos OS Evolved=14.1x53-d10
Junos OS Evolved=14.1x53-d15
Junos OS Evolved=14.1x53-d16
Junos OS Evolved=14.1x53-d20
Junos OS Evolved=14.1x53-d25
Junos OS Evolved=14.1x53-d26
Junos OS Evolved=14.1x53-d27
Junos OS Evolved=14.1x53-d30
Junos OS Evolved=14.1x53-d34
Junos OS Evolved=14.1x53-d35
Junos OS Evolved=14.1x53-d38
Junos OS Evolved=14.1x53-d40
Junos OS Evolved=14.1x53-d42
Junos OS Evolved=14.1x53-d43
Junos OS Evolved=14.1x53-d44
Junos OS Evolved=14.1x53-d45
Junos OS Evolved=14.1x53-d46
Junos OS Evolved=14.1x53-d47
Junos OS Evolved=14.1x53-d48
Junos OS Evolved=14.1x53-d49
Junos OS Evolved=14.1x53-d50
Junos OS Evolved=14.1x53-d51
Junos OS Evolved=14.1x53-d52
Junos OS Evolved=15.1x53
Junos OS Evolved=15.1x53-d10
Junos OS Evolved=15.1x53-d20
Junos OS Evolved=15.1x53-d21
Junos OS Evolved=15.1x53-d210
Junos OS Evolved=15.1x53-d230
Junos OS Evolved=15.1x53-d231
Junos OS Evolved=15.1x53-d232
Junos OS Evolved=15.1x53-d233
Junos OS Evolved=15.1x53-d234
Junos OS Evolved=15.1x53-d235
Junos OS Evolved=15.1x53-d236
Junos OS Evolved=15.1x53-d237
Junos OS Evolved=15.1x53-d25
Junos OS Evolved=15.1x53-d30
Junos OS Evolved=15.1x53-d31
Junos OS Evolved=15.1x53-d32
Junos OS Evolved=15.1x53-d33
Junos OS Evolved=15.1x53-d34
Junos OS Evolved=15.1x53-d40
Junos OS Evolved=15.1x53-d45
Junos OS Evolved=15.1x53-d47
Junos OS Evolved=15.1x53-d470
Junos OS Evolved=15.1x53-d471
Junos OS Evolved=15.1x53-d48
Junos OS Evolved=15.1x53-d490
Junos OS Evolved=15.1x53-d495
Junos OS Evolved=15.1x53-d50
Junos OS Evolved=15.1x53-d51
Junos OS Evolved=15.1x53-d52
Junos OS Evolved=15.1x53-d55
Junos OS Evolved=15.1x53-d56
Junos OS Evolved=15.1x53-d57
Junos OS Evolved=15.1x53-d58
Junos OS Evolved=15.1x53-d59
Junos OS Evolved=15.1x53-d590
Junos OS Evolved=15.1x53-d591
Junos OS Evolved=15.1x53-d592
Junos OS Evolved=15.1x53-d60
Junos OS Evolved=15.1x53-d61
Junos OS Evolved=15.1x53-d62
Junos OS Evolved=15.1x53-d63
Junos OS Evolved=15.1x53-d64
Junos OS Evolved=15.1x53-d65
Junos OS Evolved=15.1x53-d66
Junos OS Evolved=15.1x53-d67
Junos OS Evolved=15.1x53-d68
Junos OS Evolved=15.1x53-d69
Junos OS Evolved=15.1x53-d70
Juniper QFX10002-60C
Juniper Networks QFX-Series
Juniper Networks QFX-Series
Juniper QFX5100
Juniper QFX5110
Juniper QFX5120
Juniper Networks QFX-Series
Juniper QFX5200-32C
Juniper QFX5210-64C
Juniper QFX5220
Junos OS Evolved=14.1
Junos OS Evolved=14.1-r1
Junos OS Evolved=14.1-r2
Junos OS Evolved=14.1-r3
Junos OS Evolved=14.1-r4
Junos OS Evolved=14.1-r5
Junos OS Evolved=14.1-r6
Junos OS Evolved=14.1-r7
Junos OS Evolved=14.1-r8
Junos OS Evolved=14.1-r8-s3
Junos OS Evolved=14.1-r9
Junos OS Evolved=14.2
Junos OS Evolved=14.2-r
Junos OS Evolved=14.2-r1
Junos OS Evolved=14.2-r2
Junos OS Evolved=14.2-r3
Junos OS Evolved=14.2-r4
Junos OS Evolved=14.2-r5
Junos OS Evolved=14.2-r6
Junos OS Evolved=14.2-r7
Junos OS Evolved=14.2-r7-s6
Junos OS Evolved=14.2-r7-s7
Junos OS Evolved=14.2-r7-s8
Junos OS Evolved=14.2-r8
Junos OS Evolved=15.1
Junos OS Evolved=15.1-a1
Junos OS Evolved=15.1-f
Junos OS Evolved=15.1-f1
Junos OS Evolved=15.1-f2
Junos OS Evolved=15.1-f2-s1
Junos OS Evolved=15.1-f2-s2
Junos OS Evolved=15.1-f2-s3
Junos OS Evolved=15.1-f2-s4
Junos OS Evolved=15.1-f3
Junos OS Evolved=15.1-f4
Junos OS Evolved=15.1-f5
Junos OS Evolved=15.1-f5-s7
Junos OS Evolved=15.1-f6
Junos OS Evolved=15.1-f6-s1
Junos OS Evolved=15.1-f6-s10
Junos OS Evolved=15.1-f6-s12
Junos OS Evolved=15.1-f6-s2
Junos OS Evolved=15.1-f6-s3
Junos OS Evolved=15.1-f6-s4
Junos OS Evolved=15.1-f6-s5
Junos OS Evolved=15.1-f6-s6
Junos OS Evolved=15.1-f6-s7
Junos OS Evolved=15.1-f6-s8
Junos OS Evolved=15.1-f6-s9
Junos OS Evolved=15.1-f7
Junos OS Evolved=15.1-r
Junos OS Evolved=15.1-r1
Junos OS Evolved=15.1-r2
Junos OS Evolved=15.1-r3
Junos OS Evolved=15.1-r4
Junos OS Evolved=15.1-r4-s7
Junos OS Evolved=15.1-r4-s8
Junos OS Evolved=15.1-r4-s9
Junos OS Evolved=15.1-r5
Junos OS Evolved=15.1-r5-s1
Junos OS Evolved=15.1-r5-s3
Junos OS Evolved=15.1-r5-s5
Junos OS Evolved=15.1-r5-s6
Junos OS Evolved=15.1-r6
Junos OS Evolved=15.1-r6-s1
Junos OS Evolved=15.1-r6-s2
Junos OS Evolved=15.1-r6-s3
Junos OS Evolved=15.1-r6-s4
Junos OS Evolved=15.1-r6-s6
Junos OS Evolved=15.1-r7
Junos OS Evolved=15.1-r7-s1
Junos OS Evolved=15.1-r7-s2
Junos OS Evolved=15.1-r7-s3
Junos OS Evolved=15.1-r7-s4
Junos OS Evolved=15.1-r7-s5
Junos OS Evolved=16.1
Junos OS Evolved=16.1-r
Junos OS Evolved=16.1-r1
Junos OS Evolved=16.1-r2
Junos OS Evolved=16.1-r3
Junos OS Evolved=16.1-r3-s10
Junos OS Evolved=16.1-r3-s11
Junos OS Evolved=16.1-r3-s8
Junos OS Evolved=16.1-r4
Junos OS Evolved=16.1-r4-s12
Junos OS Evolved=16.1-r4-s2
Junos OS Evolved=16.1-r4-s3
Junos OS Evolved=16.1-r4-s4
Junos OS Evolved=16.1-r4-s6
Junos OS Evolved=16.1-r4-s8
Junos OS Evolved=16.1-r4-s9
Junos OS Evolved=16.1-r5
Junos OS Evolved=16.1-r5-s4
Junos OS Evolved=16.1-r6
Junos OS Evolved=16.1-r6-s1
Junos OS Evolved=16.1-r6-s3
Junos OS Evolved=16.1-r6-s4
Junos OS Evolved=16.1-r6-s6
Junos OS Evolved=16.1-r7
Junos OS Evolved=16.1-r7-s2
Junos OS Evolved=16.1-r7-s3
Junos OS Evolved=16.1-r7-s4
Junos OS Evolved=16.1-r7-s5
Junos OS Evolved=16.1-r7-s6
Junos OS Evolved=16.2
Junos OS Evolved=16.2-r1
Junos OS Evolved=16.2-r1-s6
Junos OS Evolved=16.2-r2
Junos OS Evolved=16.2-r2-s1
Junos OS Evolved=16.2-r2-s10
Junos OS Evolved=16.2-r2-s2
Junos OS Evolved=16.2-r2-s5
Junos OS Evolved=16.2-r2-s6
Junos OS Evolved=16.2-r2-s7
Junos OS Evolved=16.2-r2-s8
Junos OS Evolved=16.2-r2-s9
Junos OS Evolved=17.1
Junos OS Evolved=17.1-r1
Junos OS Evolved=17.1-r1-s7
Junos OS Evolved=17.1-r2
Junos OS Evolved=17.1-r2-s1
Junos OS Evolved=17.1-r2-s10
Junos OS Evolved=17.1-r2-s2
Junos OS Evolved=17.1-r2-s3
Junos OS Evolved=17.1-r2-s4
Junos OS Evolved=17.1-r2-s5
Junos OS Evolved=17.1-r2-s6
Junos OS Evolved=17.1-r2-s7
Junos OS Evolved=17.1-r2-s8
Junos OS Evolved=17.1-r2-s9
Junos OS Evolved=17.1-r3
Junos OS Evolved=17.1-r3-s1
Junos OS Evolved=17.2
Junos OS Evolved=17.2-r1
Junos OS Evolved=17.2-r1-s1
Junos OS Evolved=17.2-r1-s2
Junos OS Evolved=17.2-r1-s3
Junos OS Evolved=17.2-r1-s4
Junos OS Evolved=17.2-r1-s5
Junos OS Evolved=17.2-r1-s6
Junos OS Evolved=17.2-r1-s7
Junos OS Evolved=17.2-r1-s8
Junos OS Evolved=17.2-r2
Junos OS Evolved=17.2-r2-s11
Junos OS Evolved=17.2-r2-s4
Junos OS Evolved=17.2-r2-s6
Junos OS Evolved=17.2-r2-s7
Junos OS Evolved=17.2-r3
Junos OS Evolved=17.2-r3-s1
Junos OS Evolved=17.2-r3-s2
Junos OS Evolved=17.3
Junos OS Evolved=17.3-r1
Junos OS Evolved=17.3-r1-s1
Junos OS Evolved=17.3-r1-s4
Junos OS Evolved=17.3-r2
Junos OS Evolved=17.3-r2-s1
Junos OS Evolved=17.3-r2-s2
Junos OS Evolved=17.3-r2-s3
Junos OS Evolved=17.3-r2-s4
Junos OS Evolved=17.3-r3
Junos OS Evolved=17.3-r3-s1
Junos OS Evolved=17.3-r3-s10
Junos OS Evolved=17.3-r3-s2
Junos OS Evolved=17.3-r3-s3
Junos OS Evolved=17.3-r3-s4
Junos OS Evolved=17.3-r3-s5
Junos OS Evolved=17.3-r3-s6
Junos OS Evolved=17.4
Junos OS Evolved=17.4-r1
Junos OS Evolved=17.4-r1-s1
Junos OS Evolved=17.4-r1-s2
Junos OS Evolved=17.4-r1-s3
Junos OS Evolved=17.4-r1-s4
Junos OS Evolved=17.4-r1-s5
Junos OS Evolved=17.4-r1-s6
Junos OS Evolved=17.4-r1-s7
Junos OS Evolved=17.4-r2
Junos OS Evolved=17.4-r2-s1
Junos OS Evolved=17.4-r2-s10
Junos OS Evolved=17.4-r2-s11
Junos OS Evolved=17.4-r2-s2
Junos OS Evolved=17.4-r2-s3
Junos OS Evolved=17.4-r2-s4
Junos OS Evolved=17.4-r2-s5
Junos OS Evolved=17.4-r2-s6
Junos OS Evolved=17.4-r2-s7
Junos OS Evolved=17.4-r2-s8
Junos OS Evolved=18.1
Junos OS Evolved=18.1-r1
Junos OS Evolved=18.1-r2
Junos OS Evolved=18.1-r2-s1
Junos OS Evolved=18.1-r2-s2
Junos OS Evolved=18.1-r2-s4
Junos OS Evolved=18.1-r3
Junos OS Evolved=18.1-r3-s1
Junos OS Evolved=18.1-r3-s10
Junos OS Evolved=18.1-r3-s11
Junos OS Evolved=18.1-r3-s2
Junos OS Evolved=18.1-r3-s3
Junos OS Evolved=18.1-r3-s4
Junos OS Evolved=18.1-r3-s5
Junos OS Evolved=18.1-r3-s6
Junos OS Evolved=18.1-r3-s7
Junos OS Evolved=18.1-r3-s8
Junos OS Evolved=18.2
Junos OS Evolved=18.2-r1
Junos OS Evolved=18.2-r1
Junos OS Evolved=18.2-r1-s2
Junos OS Evolved=18.2-r1-s3
Junos OS Evolved=18.2-r1-s4
Junos OS Evolved=18.2-r1-s5
Junos OS Evolved=18.2-r2
Junos OS Evolved=18.2-r2-s1
Junos OS Evolved=18.2-r2-s2
Junos OS Evolved=18.2-r2-s3
Junos OS Evolved=18.2-r2-s4
Junos OS Evolved=18.2-r2-s5
Junos OS Evolved=18.2-r3
Junos OS Evolved=18.2-r3-s1
Junos OS Evolved=18.2-r3-s2
Junos OS Evolved=18.3
Junos OS Evolved=18.3-r1
Junos OS Evolved=18.3-r1-s1
Junos OS Evolved=18.3-r1-s2
Junos OS Evolved=18.3-r1-s3
Junos OS Evolved=18.3-r1-s4
Junos OS Evolved=18.3-r1-s5
Junos OS Evolved=18.3-r1-s6
Junos OS Evolved=18.3-r3
Junos OS Evolved=18.4-r2
Junos OS Evolved=18.4-r2-s1
Junos OS Evolved=18.4-r2-s2
Junos OS Evolved=19.1
Junos OS Evolved=19.1-r1
Junos OS Evolved=19.1-r1-s1
Junos OS Evolved=19.1-r1-s2
Junos OS Evolved=19.1-r1-s3
Junos OS Evolved=19.1-r2
Junos OS Evolved=19.2
Junos OS Evolved=19.2-r1
Junos OS Evolved=19.2-r1-s1
Junos OS Evolved=19.2-r1-s2
Juniper PTX1000
Juniper PTX10001-36MR
Juniper PTX10002
Juniper PTX10003 80C
Juniper PTX10004
Juniper PTX10008
Juniper PTX10016
Juniper PTX3000
Juniper PTX Series

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 14.1X53-D53, 15.1R7-S6, 15.1X53-D593, 16.1R7-S7, 16.2R2-S11, 16.2R3, 17.1R2-S11, 17.1R3-S2, 17.2R1-S9, 17.2R3-S3, 17.3R2-S5, 17.3R3-S7, 17.4R2-S9, 17.4R3, 18.1R3-S9, 18.2R2-S6, 18.2R3-S3, 18.3R1-S7, 18.3R2-S3, 18.3R3-S1, 18.4R1-S5, 18.4R2-S3, 18.4R3, 19.1R1-S4, 19.1R2-S1, 19.1R3, 19.2R1-S3, 19.2R2, 19.3R1, and all subsequent releases.

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Frequently Asked Questions

  • What is the severity of CVE-2021-0247?

    CVE-2021-0247 is rated as a high-severity vulnerability, allowing an attacker to bypass firewall rules.

  • How do I fix CVE-2021-0247?

    To fix CVE-2021-0247, update your Junos OS to the latest version provided by Juniper Networks.

  • What systems are affected by CVE-2021-0247?

    CVE-2021-0247 affects several versions of Junos OS, including 14.1 and 15.1 series.

  • Can CVE-2021-0247 be exploited remotely?

    Yes, CVE-2021-0247 can be exploited remotely by an attacker to bypass security protections.

  • What type of vulnerability is CVE-2021-0247?

    CVE-2021-0247 is classified as a race condition vulnerability affecting the firewall process of Junos OS.

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