CVE-2021-0208 json
Junos OS and Junos OS Evolved: In bidirectional LSP configurations, on MPLS egress router RPD may core upon receipt of specific malformed RSVP packet.
published 2021-01-15 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-2827
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 51%
- public exploits
- 0
- none known
Summary
An improper input validation vulnerability in the Routing Protocol Daemon (RPD) service of Juniper Networks Junos OS allows an attacker to send a malformed RSVP packet when bidirectional LSPs are in use, which when received by an egress router crashes the RPD causing a Denial of Service (DoS) condition. Continued receipt of the packet will sustain the Denial of Service. This issue affects: Juniper Networks Junos OS: All versions prior to 17.3R3-S10 except 15.1X49-D240 for SRX series; 17.4 versions prior to 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S4; 18.3 versions prior to 18.3R3-S2; 18.4 versions prior to 18.4R1-S8, 18.4R2-S6, 18.4R3-S2; 19.1 versions prior to 19.1R1-S5, 19.1R3-S3; 19.2 versions prior to 19.2R3; 19.3 versions prior to 19.3R2-S5, 19.3R3; 19.4 versions prior to 19.4R2-S2, 19.4R3-S1; 20.1 versions prior to 20.1R1-S4, 20.1R2; 15.1X49 versions prior to 15.1X49-D240 on SRX Series. Juniper Networks Junos OS Evolved: 19.3 versions prior to 19.3R2-S5-EVO; 19.4 versions prior to 19.4R2-S2-EVO; 20.1 versions prior to 20.1R1-S4-EVO.
Patch / fix
- Juniper Networks Junos OS 15.1X49-D240, 17.3R3-S10, 17.4R3-S2, 18.1R3-S10, 18.2R2-S7, 18.2R3-S4, 18.3R3-S2, 18.4R1-S8, 18.4R2-S6, 18.4R3-S2, 19.1R1-S5, 19.1R3-S3, 19.2R3, 19.3R2-S5, 19.3R3, 19.4R2-S2, 19.4R3-S1, 20.1R1-S4, 20.1R2
- Juniper Networks Junos OS Evolved 19.3R2-S5-EVO, 19.4R2-S2-EVO, 20.1R1-S4-EVO
Exploit prediction
0.66% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 3.3 | AV:A/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Juniper Networks Junos OS
- Juniper Networks Junos OS Evolved
Classification
- Weakness
-
- CWE-20 Improper Input Validation
References
-
kb.juniper.net
/JSA11098
vendor-advisory
-
juniper.net
/documentation/en_US/junos/topics/reference/configuration-statement/disable-edit-protocols-rsvp.html
vendor-advisory
-
juniper.net
/documentation/en_US/junos/topics/reference/configuration-statement/corouted-bidirectional-edit-protocols-mpls
vendor-advisory
Sources
- CVE List CVE-2021-0208
- NVD CVE-2021-0208
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