Is CVE-2021-0269 being actively exploited?

CVE-2021-0269 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2021-0269?

CVE-2021-0269 has a CVSS 3.1 base score of 8.8 (HIGH).

CVE-2021-0269

HIGH · CVSS 8.8EPSS 0.9%EU EUVD

The improper handling of client-side parameters in J-Web of Juniper Networks Junos OS allows an attacker to perform a number of different malicious actions against a target device when a user is authenticated to J-Web. An attacker may be able to supersede existing parameters, including hardcoded parameters within the HTTP/S session, access and exploit variables, bypass web application firewall rules or input validation mechanisms, and otherwise alter and modify J-Web's normal behavior. An attacker may be able to transition victims to malicious web services, or exfiltrate sensitive information from otherwise secure web forms. This issue affects: Juniper Networks Junos OS: All versions prior to 17.4R3-S3; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R3-S6; 19.1 versions prior to 19.1R3-S4; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2.

Key facts

CVSS score: 8.8 (v3.1)
Severity: HIGH
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-233
EPSS score: 0.9% (58th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2021-2888)
Published: April 22, 2021
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2021-2888 in the EU Vulnerability Database. Last updated in EUVD on September 17, 2024.

View on the EU Vulnerability Database

Affected products

juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos
juniper / junos

and 98 more…

Certified products that may be affected

1 FIPS 140 or Common Criteria certified product, from automated matching by sec-certs.org.

Junos Space Network Management Platform, with or without Network Director and with or without Security Director in JA2500 - Juniper Networks, Inc. - FIPS 140 3816 - historical

References

https://kb.juniper.net/JSA11160(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

Query CVEs from your AI assistant

The CVE/NVD Explorer brain answers CVE questions directly inside Claude, ChatGPT, or any MCP assistant — always up to date, no setup. Add it once and stop pasting advisories into chat.

Add the CVE brain