CVE-2021-0275highCWE-79

CVE-2021-0275: high-severity vulnerability in Juniper Networks Junos OS

Junos OS: J-Web: Cross-site scripting attack allows an attacker to gain control of another users session.

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.8epss 1.2%
A Cross-site Scripting (XSS) vulnerability in J-Web on Juniper Networks Junos OS allows an attacker to target another user's session thereby gaining access to the users session. The other user session must be active for the attack to succeed. Once successful, the attacker has the same privileges as the user. If the user has root privileges, the attacker may be able to gain full control of the device. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15 on EX Series; 12.3X48 versions prior to 12.3X48-D95 on SRX Series; 15.1 versions prior to 15.1R7-S6 on EX Series; 15.1X49 versions prior to 15.1X49-D200 on SRX Series; 16.1 versions prior to 16.1R7-S7; 16.2 versions prior to 16.2R2-S11, 16.2R3; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S7; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S9; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3-S1; 18.4 versions prior to 18.4R1-S6, 18.4R2-S4, 18.4R3; 19.1 versions prior to 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S3, 19.2R2; 19.3 versions prior to 19.3R2.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
Juniper Networks · Junos OS
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CVE-2023-36845CRITICALJunos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to control an important environment variableEPSS 95.1%KEVCVE-2023-36846MEDIUMJunos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary filesEPSS 93.5%KEVCVE-2023-36844MEDIUMJunos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variablesEPSS 90.0%KEVCVE-2023-36847MEDIUMJunos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary filesEPSS 83.5%KEVCVE-2020-1631HIGHOut of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) servicesEPSS 4.9%KEVCVE-2025-21590MEDIUMJunos OS: An local attacker with shell access can execute arbitrary codeEPSS 1.7%KEV