CVE-2021-31363: Junos OS and Junos OS Evolved: Receipt of a specific LDP message will cause a Denial of Service
First published: Tue Oct 19 2021(Updated: )
In an MPLS P2MP environment a Loop with Unreachable Exit Condition vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause high load on RPD which in turn may lead to routing protocol flaps. If a system with sensor-based-stats enabled receives a specific LDP FEC this can lead to the above condition. Continued receipted of such an LDP FEC will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 version 19.2R2 and later 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-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R2. Juniper Networks Junos OS Evolved All versions prior to 20.1R2-S3-EVO; 20.3 versions prior to 20.3R1-S2-EVO.
Credit: sirt@juniper.net
| Affected Software | Affected Version | How to fix |
|---|---|---|
| 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-s2 | |
| 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-s4 | |
| 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-r3 | |
| 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-r3 | |
| Juniper JUNOS | =20.3-r1 | |
| Juniper JUNOS | =20.3-r1-s1 | |
| Juniper JUNOS | =20.3-r2 | |
| Juniper Junos Os Evolved | =20.1-r1 | |
| Juniper Junos Os Evolved | =20.1-r1-s1 | |
| Juniper Junos Os Evolved | =20.1-r2 | |
| Juniper Junos Os Evolved | =20.1-r2-s1 | |
| Juniper Junos Os Evolved | =20.1-r2-s2 | |
| Juniper Junos Os Evolved | =20.2-r1 | |
| Juniper Junos Os Evolved | =20.2-r1-s1 | |
| Juniper Junos Os Evolved | =20.2-r2 | |
| Juniper Junos Os Evolved | =20.3-r1 | |
| Juniper Junos Os Evolved | =20.3-r1-s1 |
Remedy
The following software releases have been updated to resolve this specific issue in Junos OS: 19.2R3-S3, 19.3R2-S6, 19.3R3-S2, 19.4R1-S4, 19.4R2-S4, 19.4R3-S2, 20.1R2-S1, 20.1R3, 20.2R2-S1, 20.2R3, 20.3R1-S2, 20.3R2, 20.4R1, and all subsequent releases. The following software releases have been updated to resolve this specific issue in Junos OS Evolved: 20.1R2-S3-EVO, 20.3R1-S2-EVO, 20.4R1-EVO, and all subsequent releases.
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Reference Links
- collector/nvd-index
- agent/type
- agent/softwarecombine
- collector/mitre-cve
- source/MITRE
- agent/last-modified-date
- agent/author
- agent/weakness
- agent/references
- agent/title
- agent/severity
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- agent/tags
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- agent/event
- vendor/juniper
- canonical/juniper junos
- version/juniper junos/19.2-r2
- version/juniper junos/19.2-r2-s1
- version/juniper junos/19.2-r3
- version/juniper junos/19.2-r3-s1
- version/juniper junos/19.2-r3-s2
- version/juniper junos/19.3
- version/juniper junos/19.3-r1
- version/juniper junos/19.3-r1-s1
- version/juniper junos/19.3-r2
- version/juniper junos/19.3-r2-s1
- version/juniper junos/19.3-r2-s2
- version/juniper junos/19.3-r2-s3
- version/juniper junos/19.3-r2-s4
- version/juniper junos/19.3-r2-s5
- version/juniper junos/19.3-r3-s2
- version/juniper junos/19.4-r1
- version/juniper junos/19.4-r1-s1
- version/juniper junos/19.4-r1-s2
- version/juniper junos/19.4-r1-s3
- version/juniper junos/19.4-r2-s4
- version/juniper junos/19.4-r3-s2
- version/juniper junos/20.1-r1
- version/juniper junos/20.1-r1-s1
- version/juniper junos/20.1-r1-s2
- version/juniper junos/20.1-r1-s3
- version/juniper junos/20.1-r1-s4
- version/juniper junos/20.1-r2
- version/juniper junos/20.1-r3
- version/juniper junos/20.2-r1
- version/juniper junos/20.2-r1-s1
- version/juniper junos/20.2-r1-s2
- version/juniper junos/20.2-r1-s3
- version/juniper junos/20.2-r2
- version/juniper junos/20.2-r3
- version/juniper junos/20.3-r1
- version/juniper junos/20.3-r1-s1
- version/juniper junos/20.3-r2
- canonical/juniper junos os evolved
- version/juniper junos os evolved/20.1-r1
- version/juniper junos os evolved/20.1-r1-s1
- version/juniper junos os evolved/20.1-r2
- version/juniper junos os evolved/20.1-r2-s1
- version/juniper junos os evolved/20.1-r2-s2
- version/juniper junos os evolved/20.2-r1
- version/juniper junos os evolved/20.2-r1-s1
- version/juniper junos os evolved/20.2-r2
- version/juniper junos os evolved/20.3-r1
- version/juniper junos os evolved/20.3-r1-s1