CVE-2021-0208
lowpriority · track · 13EPSS 0.007 · 51 %ileEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.3–8.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (49)
Products and version ranges known to be affected.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (13)
External citations — patches, advisories, analysis.
- https://kb.juniper.net/InfoCenter/index?page=content&id=JSA11098&actp=LIST_RECENTPatchcnnvd
- https://kb.juniper.net/JSA11098cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-0208cnnvd
- https://vigilance.fr/vulnerability/Junos-OS-denial-of-service-via-Bidirectional-LSP-RSVP-34328cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.0176/cnnvd
- https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/corouted-bidirectional-edit-protocols-mpls.htmlcnnvd
- https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/disable-edit-protocols-rsvp.htmlcnnvd
- https://kb.juniper.net/JSA11098enisa_euvd
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