CVE-2020-1601: Certain types of malformed Path Computation Element Protocol (PCEP) packets when received and processed by a Juniper Networks Junos OS device serving as a Path

Certain types of malformed Path Computation Element Protocol (PCEP) packets when received and processed by a Juniper Networks Junos OS device serving as a Path

Certain types of malformed Path Computation Element Protocol (PCEP) packets when received and processed by a Juniper Networks Junos OS device serving as a Path Computation Client (PCC) in a PCEP environment using Juniper's path computational element protocol daemon (pccd) process allows an attacker to cause the pccd process to crash and generate a core file thereby causing a Denial of Service (DoS). Continued receipt of this family of malformed PCEP packets will cause an extended Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 15.1 versions prior to 15.1F6-S13, 15.1R7-S4; 15.1X49 versions prior to 15.1X49-D180 on SRX Series; 15.1X53 versions prior to 15.1X53-D238, 15.1X53-D496, 15.1X53-D592; 16.1 versions prior to 16.1R7-S4; 16.2 versions prior to 16.2R2-S9; 17.1 versions prior to 17.1R2-S11, 17.1R3; 17.2 versions prior to 17.2R1-S9; 17.2 version 17.2R2 and later prior to 17.2R3-S2; 17.3 versions prior to 17.3R3-S3; 17.4 versions prior to 17.4R2-S2, 17.4R3; 18.1 versions prior to 18.1R3-S2; 18.2 versions prior to 18.2R2-S6, 18.2R3; 18.2X75 versions prior to 18.2X75-D40; 18.3 versions prior to 18.3R2; 18.4 versions prior to 18.4R1-S2, 18.4R2. This i

Description from the National Vulnerability Database, published by sirt@juniper.net

What it means for a small business

Junos OS is network equipment or remote-access software: the box between your office and the internet. These are a favorite target because breaking one opens the whole office.

If an IT provider set it up, ask them to confirm the firmware version and the date it was updated. If nobody looks after it, that's the bigger problem.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.1%, higher than 64% of CVEs. That’s above average: worth scheduling this week. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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