CVE-2021-0267

Junos OS: Receipt of a crafted DHCP packet will cause the jdhcpd DHCP service to core.

Description

An Improper Input Validation vulnerability in the active-lease query portion in JDHCPD's DHCP Relay Agent of Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) by sending a crafted DHCP packet to the device thereby crashing the jdhcpd DHCP service. This is typically configured for Broadband Subscriber Sessions. Continued receipt and processing of this crafted packet will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS: 19.4 versions prior to 19.4R3-S1; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R2. This issue does not affect Junos OS Evolved.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 19.4R3-S1, 20.1R2-S1, 20.1R3, 20.2R3, 20.3R2, 20.4R1, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.06%
Vendor Advisory juniper.net Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11158 vendor advisory
https://www.juniper.net/documentation/us/en/software/junos/subscriber-mgmt-sessions/topics/ref/statement/active-leasequery-edit-forwarding-options.html vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0267?
CVE-2021-0267 has been scored as a high severity vulnerability.
How to fix CVE-2021-0267?
To fix CVE-2021-0267: The following software releases have been updated to resolve this specific issue: Junos OS: 19.4R3-S1, 20.1R2-S1, 20.1R3, 20.2R3, 20.3R2, 20.4R1, and all subsequent releases.
Is CVE-2021-0267 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0267 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0267?
CVE-2021-0267 affects Juniper Networks Junos OS.
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