CVE-2020-1631 | Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services

Exp

A vulnerability in the HTTP/HTTPS service used by J-Web, Web Authentication, Dynamic-VPN (DVPN), Firewall Authentication Pass-Through with Web-Redirect, and Zero Touch Provisioning (ZTP) allows an unauthenticated attacker to perform local file inclusion (LFI) or path traversal. Using this vulnerability, an attacker may be able to inject commands into the httpd.log, read files with 'world' readable permission file or obtain J-Web session tokens. In the case of command injection, as the HTTP service runs as user 'nobody', the impact of this command injection is limited. (CVSS score 5.3, vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N) In the case of reading files with 'world' readable permission, in Junos OS 19.3R1 and above, the unauthenticated attacker would be able to read the configuration file. (CVSS score 5.9, vector CVSS:3.1/ AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N) If J-Web is enabled, the attacker could gain the same level of access of anyone actively logged into J-Web. If an administrator is logged in, the attacker could gain administrator access to J-Web. (CVSS score 8.8, vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) This issue only affects Juniper Networks Junos OS devices with HTTP/HTTPS services enabled. 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 To summarize: If HTTP/HTTPS services are disabled, there is no impact from this vulnerability. If HTTP/HTTPS services are enabled and J-Web is not in use, this vulnerability has a CVSS score of 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N). If J-Web is enabled, this vulnerability has a CVSS score of 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Juniper SIRT has received a single report of this vulnerability being exploited in the wild. Out of an abundance of caution, we are notifying customers so they can take appropriate actions. Indicators of Compromise: The /var/log/httpd.log may have indicators that commands have injected or files being accessed. The device administrator can look for these indicators by searching for the string patterns "=*;*&" or "*%3b*&" in /var/log/httpd.log, using the following command: user@device> show log httpd.log | match "=*;*&|=*%3b*&" If this command returns any output, it might be an indication of malicious attempts or simply scanning activities. Rotated logs should also be reviewed, using the following command: user@device> show log httpd.log.0.gz | match "=*;*&|=*%3b*&" user@device> show log httpd.log.1.gz | match "=*;*&|=*%3b*&" Note that a skilled attacker would likely remove these entries from the local log file, thus effectively eliminating any reliable signature that the device had been attacked. This issue affects Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S16; 12.3X48 versions prior to 12.3X48-D101, 12.3X48-D105; 14.1X53 versions prior to 14.1X53-D54; 15.1 versions prior to 15.1R7-S7; 15.1X49 versions prior to 15.1X49-D211, 15.1X49-D220; 16.1 versions prior to 16.1R7-S8; 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S4; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R3-S2 ; 18.4 version 18.4R2 and later versions; 19.1 versions prior to 19.1R1-S5, 19.1R3-S1; 19.1 version 19.1R2 and later versions; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R2-S3, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2; 20.1 versions prior to 20.1R1-S1, 20.1R2.

Published: 2020-05-04 Last update: 2025-10-24 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-1631 is rated Critical Active Threat (91.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 5.40%). Core evidence: CISA KEV confirms active exploitation (added 2022-03-25) affecting Juniper / Junos OS. a weakness (CWE-22) Unauthenticated remote administrative access may be possible. Mandatory action: The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2020-1631

Name: Juniper Junos OS Path Traversal Vulnerability · CISA KEV detail

Exploit added: 2022-03-25

Action due: 2022-04-15

Required action: Apply updates per vendor instructions.

Exploit prediction scoring system (EPSS) score for CVE-2020-1631

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-23 5.30% 5.40% +0.10%
2 2025-11-21 7.36% 5.30% -2.06%
3 2025-11-18 7.36%

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-1631

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
8.6 6.4 [email protected]

Weakness enumeration for CVE-2020-1631

Affected software / configurations for CVE-2020-1631

Vendor Product Version Raw CPE
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:-:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r1:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r10:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r10-s1:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r10-s2:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r11:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s1:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s11:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s12:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s13:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s14:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s15:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s3:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s4:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s6:*:*:*:*:*:*
juniper junos 12.3 cpe:2.3:o:juniper:junos:12.3:r12-s8:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:-:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d10:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d100:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d15:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d20:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d25:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d30:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d35:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d40:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d45:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d50:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d51:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d55:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d60:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d65:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d70:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d75:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d80:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d85:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d90:*:*:*:*:*:*
juniper junos 12.3x48 cpe:2.3:o:juniper:junos:12.3x48:d95:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:-:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d10:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d15:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d16:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d25:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d26:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d27:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d30:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d35:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d40:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d42:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d43:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d44:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d45:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d46:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d47:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d48:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d49:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d50:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d51:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d52:*:*:*:*:*:*
juniper junos 14.1x53 cpe:2.3:o:juniper:junos:14.1x53:d53:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:-:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:a1:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f1:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f2:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f2-s1:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f2-s2:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f2-s3:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f2-s4:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f3:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f4:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f5:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f5-s7:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6-s1:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6-s12:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6-s2:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6-s3:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6-s4:*:*:*:*:*:*
juniper junos 15.1 cpe:2.3:o:juniper:junos:15.1:f6-s7:*:*:*:*:*:*

References for CVE-2020-1631

cvelogic Threat Intelligence