CVE-2020-1626
Junos OS Evolved: Denial of Service vulnerability in processing high rate of specific packets
- Published
- Updated
- Reserved
- Assigned by
- juniper
Description
A vulnerability in Juniper Networks Junos OS Evolved may allow an attacker to cause a Denial of Service (DoS) by sending a high rate of specific packets to the device, resulting in a pfemand process crash. The pfemand process is responsible for packet forwarding on the device. By continuously sending the packet flood, an attacker can repeatedly crash the pfemand process causing a sustained Denial of Service. This issue can only be triggered by traffic sent to the device. Transit traffic does not cause this issue. This issue affects all version of Junos OS Evolved prior to 19.1R1-EVO.
Timeline
ID reserved
By juniper
- 5 months later
· 5 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| juniperCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.4% · top 28% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
- Denial of Service
Affected products
Juniper Networks · Junos OS Evolved
- affected unspecified – < 19.1R1-EVO
What to do
Solution: The following software releases have been updated to resolve this specific issue: 19.1R1-EVO, 19.2R1-EVO, 19.3R1-EVO, and all subsequent releases.
Workaround: Use access lists or firewall filters to limit access to the device to known TCP and UDP ports, and only from trusted, administrative networks or hosts.
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References (2)
- https://tools.ietf.org/html/rfc6192 (opens in a new tab)x_refsource_MISCx_transferred
- https://kb.juniper.net/JSA11005 (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-1626)Record last updated .