CVE-2021-0226 json
Junos OS Evolved: The IPv6 BGP session will flap due to receipt of a specific IPv6 packet
published 2021-04-22 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-2845
- cvss
- 7.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 59%
- public exploits
- 0
- none known
Summary
On Juniper Networks Junos OS Evolved devices, receipt of a specific IPv6 packet may cause an established IPv6 BGP session to terminate, creating a Denial of Service (DoS) condition. Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue does not affect IPv4 BGP sessions. This issue affects IBGP or EBGP peer sessions with IPv6. This issue affects: Juniper Networks Junos OS Evolved: 19.4 versions prior to 19.4R2-S3-EVO; 20.1 versions prior to 20.1R2-S3-EVO; 20.2 versions prior to 20.2R2-S1-EVO; 20.3 versions prior to 20.3R2-EVO. This issue does not affect Juniper Networks Junos OS releases.
Patch / fix
- Juniper Networks Junos OS Evolved 19.4R2-S3-EVO, 20.1R2-S3-EVO, 20.2R2-S1-EVO, 20.3R2-EVO
Exploit prediction
0.88% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.1 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Juniper Networks Junos OS Evolved
Classification
- Weakness
-
- CWE-665 Improper Initialization
References
-
kb.juniper.net
/JSA11121
vendor-advisory
Sources
- CVE List CVE-2021-0226
- NVD CVE-2021-0226
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