CVE-2020-1671 Junos OS: Receipt of malformed DHCPv6 packets causes jdhcpd to crash.
Malformed DHCPv6 packets crash the JDHCPD daemon on Junos OS devices configured as DHCPv6 servers or relays, causing service disruption.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2020-1671?
CVE-2020-1671 is a high-severity denial of service vulnerability in Juniper Junos, published on 16 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
On Juniper Networks Junos OS platforms configured as DHCPv6 local server or DHCPv6 Relay Agent, Juniper Networks Dynamic Host Configuration Protocol Daemon (JDHCPD) process might crash with a core dump if a malformed DHCPv6 packet is received, resulting with the restart of the daemon. This issue only affects DHCPv6, it does not affect DHCPv4. This issue affects: Juniper Networks Junos OS 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.2X75 versions prior to 18.2X75-D65; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R3-S2; 19.2 versions prior to 19.2R1-S5, 19.2R3; 19.2 version 19.2R2 and later versions; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R1-S3, 20.1R2; This issue does not affect Juniper Networks Junos OS prior to 17.4R1.
Which versions are affected by CVE-2020-1671?
It affects 1 product.
Products include Juniper Junos.
How do I fix CVE-2020-1671?
No fix has been published for CVE-2020-1671 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2020-1671 being exploited?
There is no known exploitation of CVE-2020-1671 in the wild and no public exploit code.
Other vulnerabilities in Juniper Junos
- CVE-2023-36845 Juniper Junos OS EX Series and SRX Series PHP External Variable Modification
- CVE-2020-1631 Juniper Junos OS Path Traversal
- CVE-2025-21590 Juniper Junos OS Improper Isolation or Compartmentalization
- CVE-2023-36851 Juniper Junos OS SRX Series Missing Authentication for Critical Function
- CVE-2023-36844 Juniper Junos OS EX Series PHP External Variable Modification
Sources
Also known as GHSA-cx8w-wg7g-8xjv.