Junos OS: Kernel crash (vmcore) upon receipt of a malformed IPv6 packet.
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-415 and the CVSS impact.
Summary
On Juniper Networks Junos OS devices, receipt of a malformed IPv6 packet may cause the system to crash and restart (vmcore). This issue can be trigged by a malformed IPv6 packet destined to the Routing Engine. An attacker can repeatedly send the offending packet resulting in an extended Denial of Service condition. Only IPv6 packets can trigger this issue. IPv4 packets cannot trigger this issue. This issue affects Juniper Networks Junos OS 18.4 versions prior to 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS prior to 18.4R1.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Juniper | Junos OS | 18.4 to before 18.4R2-S4, 18.4R3-S1; 19.1 to before 19.1R2-S1, 19.1R3; 19.2 to before 19.2R1-S5, 19.2R2; 19.3 to before 19.3R2-S4, 19.3R3; 19.4 to before 19.4R1-S3, 19.4R2 | 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2 | Patch available | CNA |
- Junos OS VendorJuniper Affected 18.4 to before 18.4R2-S4, 18.4R3-S1; 19.1 to before 19.1R2-S1, 19.1R3; 19.2 to before 19.2R1-S5, 19.2R2; 19.3 to before 19.3R2-S4, 19.3R3; 19.4 to before 19.4R1-S3, 19.4R2 Fixed in 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2 Patch available CNA
CPE configurations NVD · 34
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:juniper:junos:18.4:-:*:*:*:*:*:* | 18.4 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r1:*:*:*:*:*:* | 18.4 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r1-s1:*:*:*:*:*:* | 18.4 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r1-s2:*:*:*:*:*:* | 18.4 r1-s2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r1-s5:*:*:*:*:*:* | 18.4 r1-s5 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r1-s6:*:*:*:*:*:* | 18.4 r1-s6 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r2:*:*:*:*:*:* | 18.4 r2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r2-s1:*:*:*:*:*:* | 18.4 r2-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r2-s2:*:*:*:*:*:* | 18.4 r2-s2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:18.4:r2-s3:*:*:*:*:*:* | 18.4 r2-s3 | Vulnerable | Juniper |
- cpe:2.3:o:juniper:junos:18.4:-:*:*:*:*:*:* Versions 18.4 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r1:*:*:*:*:*:* Versions 18.4 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r1-s1:*:*:*:*:*:* Versions 18.4 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r1-s2:*:*:*:*:*:* Versions 18.4 r1-s2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r1-s5:*:*:*:*:*:* Versions 18.4 r1-s5 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r1-s6:*:*:*:*:*:* Versions 18.4 r1-s6 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r2:*:*:*:*:*:* Versions 18.4 r2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r2-s1:*:*:*:*:*:* Versions 18.4 r2-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r2-s2:*:*:*:*:*:* Versions 18.4 r2-s2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:18.4:r2-s3:*:*:*:*:*:* Versions 18.4 r2-s3 Vulnerable ·Juniper
Show 24 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:juniper:junos:18.4:r3:*:*:*:*:*:* | 18.4 r3 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:-:*:*:*:*:*:* | 19.1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:r1:*:*:*:*:*:* | 19.1 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:r1-s1:*:*:*:*:*:* | 19.1 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:r1-s2:*:*:*:*:*:* | 19.1 r1-s2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:r1-s3:*:*:*:*:*:* | 19.1 r1-s3 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:r1-s4:*:*:*:*:*:* | 19.1 r1-s4 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.1:r2:*:*:*:*:*:* | 19.1 r2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.2:-:*:*:*:*:*:* | 19.2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.2:r1:*:*:*:*:*:* | 19.2 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.2:r1-s1:*:*:*:*:*:* | 19.2 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.2:r1-s2:*:*:*:*:*:* | 19.2 r1-s2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.2:r1-s3:*:*:*:*:*:* | 19.2 r1-s3 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.2:r1-s4:*:*:*:*:*:* | 19.2 r1-s4 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:-:*:*:*:*:*:* | 19.3 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:r1:*:*:*:*:*:* | 19.3 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:r1-s1:*:*:*:*:*:* | 19.3 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:r2:*:*:*:*:*:* | 19.3 r2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:r2-s1:*:*:*:*:*:* | 19.3 r2-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:r2-s2:*:*:*:*:*:* | 19.3 r2-s2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.3:r2-s3:*:*:*:*:*:* | 19.3 r2-s3 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.4:r1:*:*:*:*:*:* | 19.4 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.4:r1-s1:*:*:*:*:*:* | 19.4 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:19.4:r1-s2:*:*:*:*:*:* | 19.4 r1-s2 | Vulnerable | Juniper |
- cpe:2.3:o:juniper:junos:18.4:r3:*:*:*:*:*:* Versions 18.4 r3 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:-:*:*:*:*:*:* Versions 19.1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:r1:*:*:*:*:*:* Versions 19.1 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:r1-s1:*:*:*:*:*:* Versions 19.1 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:r1-s2:*:*:*:*:*:* Versions 19.1 r1-s2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:r1-s3:*:*:*:*:*:* Versions 19.1 r1-s3 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:r1-s4:*:*:*:*:*:* Versions 19.1 r1-s4 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.1:r2:*:*:*:*:*:* Versions 19.1 r2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.2:-:*:*:*:*:*:* Versions 19.2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.2:r1:*:*:*:*:*:* Versions 19.2 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.2:r1-s1:*:*:*:*:*:* Versions 19.2 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.2:r1-s2:*:*:*:*:*:* Versions 19.2 r1-s2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.2:r1-s3:*:*:*:*:*:* Versions 19.2 r1-s3 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.2:r1-s4:*:*:*:*:*:* Versions 19.2 r1-s4 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:-:*:*:*:*:*:* Versions 19.3 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:r1:*:*:*:*:*:* Versions 19.3 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:r1-s1:*:*:*:*:*:* Versions 19.3 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:r2:*:*:*:*:*:* Versions 19.3 r2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:r2-s1:*:*:*:*:*:* Versions 19.3 r2-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:r2-s2:*:*:*:*:*:* Versions 19.3 r2-s2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.3:r2-s3:*:*:*:*:*:* Versions 19.3 r2-s3 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.4:r1:*:*:*:*:*:* Versions 19.4 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.4:r1-s1:*:*:*:*:*:* Versions 19.4 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:19.4:r1-s2:*:*:*:*:*:* Versions 19.4 r1-s2 Vulnerable ·Juniper
Remediation
- Fix · CNA Junos OS (Juniper Networks) Fixed in 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2
Timeline
- 2026-10-02 Threatist record created from CVE-2020-1686
- 2026-10-03 Alias added: GHSA-2j3x-ghj2-35fv
References
Advisory 1
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Sources
- CVE-2020-1686 · CVE Program
- CVE-2020-1686 · NVD
- FIRST EPSS
- GHSA-2j3x-ghj2-35fv · GitHub Advisory Database · CC BY 4.0
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