CVE-2020-1673Junos OS: Reflected Cross-site Scripting vulnerability in J-Web and web based (HTTP/HTTPS) services
- 8.8HighCVSS base score
- 1.6%Exploitation in 30 daysEPSS · top 24% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Insufficient Cross-Site Scripting (XSS) protection in Juniper Networks J-Web and web based (HTTP/HTTPS) services allows an unauthenticated attacker to hijack the target user's HTTP/HTTPS session and perform administrative actions on the Junos device as the targeted user. This issue only affects Juniper Networks Junos OS devices with HTTP/HTTPS services enabled such as J-Web, Web Authentication, Dynamic-VPN (DVPN), Firewall Authentication Pass-Through with Web-Redirect, and Zero Touch Provisioning (ZTP). Junos OS devices with HTTP/HTTPS services disabled are not affected. If HTTP/HTTPS services are enabled, the following command will show the httpd processes: user@device> show system processes | match http 5260 - S 0:00.13 /usr/sbin/httpd-gk -N 5797 - I 0:00.10 /usr/sbin/httpd --config /jail/var/etc/httpd.conf In order to successfully exploit this vulnerability, the attacker needs to convince the device administrator to take action such as clicking the crafted URL sent via phishing email or convince the administrator to input data in the browser console. This issue affects Juniper Networks Junos OS: 18.1 versions prior to 18.1R3-S1; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R2-S5, 18.4R3-S2; 19.1 versions prior to 19.1R2-S2, 19.1R3-S1; 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; 20.1 versions prior to 20.1R1-S2, 20.1R2. This issue does not affect Juniper Networks Junos OS prior to 18.1R1.
Timeline
ID reserved
By juniper
- 12 months later
· 12 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 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.6% · top 24% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Affected products
- unaffected unspecified – < 18.1R1
- affected 18.1 – < 18.1R3-S11
- affected 18.2 – < 18.2R3-S5
- affected 18.3 – < 18.3R2-S4, 18.3R3-S2
- affected 18.4 – < 18.4R2-S5, 18.4R3-S2
- affected 19.1 – < 19.1R2-S2, 19.1R3-S1
- affected 19.2 – < 19.2R1-S5, 19.2R2
- affected 19.3 – < 19.3R2-S4, 19.3R3
- affected 19.4 – < 19.4R1-S3, 19.4R2
- affected 20.1 – < 20.1R1-S2, 20.1R2
What to do
Solution: The following software releases have been updated to resolve this specific issue: Junos OS 18.1R3-S11, 18.2R3-S5, 18.3R2-S4, 18.3R3-S2, 18.4R2-S5, 18.4R3-S2, 19.1R2-S2, 19.1R3-S1, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1-S2, 20.1R2, 20.2R1 and all subsequent releases.
Workaround: There are no viable workarounds for this issue.
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References
References1
- https://kb.juniper.net/JSA11070 (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)
- EUVD EUVD-2020-12535 (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://cveledger.app/cve/CVE-2020-1673)Record last updated .