Actively exploited in the wild
Juniper Junos OS Path Traversal Vulnerability
Juniper - Junos OS · Listed in the CISA KEV since 2022-03-25. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2020-1631
HighCVSS 8.8KEVSummary
A vulnerability in the HTTP/HTTPS service used by J-Web, Web Authentication, DVPN, Firewall Authentication Pass-Through with Web-Redirect, and ZTP allows an unauthenticated attacker to perform local file inclusion (LFI) or path traversal. An attacker may inject commands into httpd.log, read world-readable files, or obtain J-Web session tokens. If J-Web is enabled, the attacker could gain the same access level as a logged-in administrator.
Risk Assessment
The vulnerability can lead to disclosure of sensitive information, including configuration files, and in the case of an active J-Web administrator session, full compromise of the device. There is a report of this vulnerability being exploited in the wild.
Recommendation
Immediately upgrade Junos OS to a fixed version (as listed in the description) or disable HTTP/HTTPS services if not in use. Additionally, search /var/log/httpd.log for patterns '=*;*&' or '*%3b*&' to detect exploitation attempts.
Other vulnerabilities in Junos OS
See all- CVE-2026-21917High
A vulnerability in the Web-Filtering module of Junos OS on SRX Series allows an unauthenticated network-based attacker to cause a Denial-of-Service (DoS). A specially crafted SSL packet causes an FPC crash and restart.
- CVE-2026-21913High
A vulnerability in Juniper Junos OS on EX4000 models with 48 ports (EX4000-48T, EX4000-48P, EX4000-48MP) allows an unauthenticated network-based attacker to cause an FXPC crash and restart by sending a high volume of traffic to the device. This leads to a complete service outage until the device automatically restarts.
- CVE-2026-21905High
A vulnerability in Junos OS on SRX and MX devices with MX-SPC3 or MS-MPC service cards causes an infinite loop in the flow management process (flowd or mspmand) after receiving specific SIP messages over TCP. An unauthenticated attacker can send multiple such messages, leading to watchdog timer expiration and process crash, resulting in a Denial of Service (DoS). The issue only occurs over TCP, not UDP.
- CVE-2025-60003High
A Buffer Over-read vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). When an affected device receives a BGP update with a set of specific optional transitive attributes over an established peering session, rpd will crash and restart when attempting to advertise the received information to another peer.
- CVE-2025-59960High
A vulnerability in the DHCP service (jdhcpd) of Junos OS and Junos OS Evolved allows a DHCP client in one subnet to exhaust the address pools of other subnets, leading to a Denial of Service (DoS) on the downstream DHCP server. The issue arises from improper handling of DHCP DISCOVER packets with Option 82 in 'forward-only' mode, which are forwarded unmodified instead of being dropped, consuming addresses from the pool.
- CVE-2016-4922High
A vulnerability in Junos OS allows unauthorized access to the operating system through certain combinations of CLI commands. Users with the appropriate permissions can achieve elevated privileges and gain complete control of the device.
- CVE-2017-2344High
An internal Junos OS sockets library is vulnerable to a buffer overflow, which may lead to a denial of service (kernel panic) or privilege escalation through local code execution. The routines are only accessible via programs running on the device.
- CVE-2017-2303High
On Juniper Networks products or platforms running Junos OS versions prior to 12.1X46-D50, 12.1X47-D40, 12.3R13, 12.3X48-D30, 13.2X51-D40, 13.3R10, 14.1R8, 14.1X53-D35, 14.1X55-D35, 14.2R5, 15.1F6, 15.1R3, 15.1X49-D30, 15.1X49-D40, 15.1X53-D35, where RIP is enabled, certain RIP advertisements may cause the RPD daemon to crash, resulting in a denial of service condition.
- CVE-2017-2302High
On Juniper Networks products running Junos OS versions prior to 12.1X46-D55, 12.1X47-D45, 12.3R13, 12.3X48-D35, 13.3R10, 14.1R8, 14.1X53-D40, 14.1X55-D35, 14.2R6, 15.1F2 or 15.1R1, where the BGP add-path feature is enabled with 'send' option or with both 'send' and 'receive' options, a network-based attacker can cause the rpd daemon to crash and restart. Repeated crashes of the rpd daemon can result in an extended denial of service condition.
- CVE-2017-2301High
On Juniper Networks products running Junos OS versions prior to 11.4R13-S3, 12.1X46-D60, 12.3R12-S2, 13.2X51-D40, 13.3R10, 14.1R8, 14.1X53-D12, 14.1X55-D35, 14.2R7, 15.1F6, 15.1R3, 15.1X49-D60, and 15.1X53-D30, when DHCPv6 is enabled, receiving a crafted DHCPv6 packet causes the jdhcpd daemon to crash and restart. Repeated crashes of the jdhcpd process may lead to an extended denial of service condition for subscribers attempting to obtain IPv6 addresses.
Original NVD description (English source)
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.