CVE-2024-21606

Junos OS: SRX Series: When "tcp-encap" is configured and specific packets are received flowd will crash

Description

A Double Free vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX Series allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS). In a remote access VPN scenario, if a "tcp-encap-profile" is configured and a sequence of specific packets is received, a flowd crash and restart will be observed. This issue affects Juniper Networks Junos OS on SRX Series: * All versions earlier than 20.4R3-S8; * 21.2 versions earlier than 21.2R3-S6; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S5; * 22.1 versions earlier than 22.1R3-S3; * 22.2 versions earlier than 22.2R3-S3; * 22.3 versions earlier than 22.3R3-S1; * 22.4 versions earlier than 22.4R2-S2, 22.4R3.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S8, 21.2R3-S6, 21.3R3-S5, 21.4R3-S5, 22.1R3-S3, 22.2R3-S3, 22.3R3-S1, 22.4R2-S2, 22.4R3, 23.2R1, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.18%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA75747 vendor advisory
https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H technical description third party advisory

Frequently Asked Questions

What is the severity of CVE-2024-21606?
CVE-2024-21606 has been scored as a high severity vulnerability.
How to fix CVE-2024-21606?
To fix CVE-2024-21606: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S8, 21.2R3-S6, 21.3R3-S5, 21.4R3-S5, 22.1R3-S3, 22.2R3-S3, 22.3R3-S1, 22.4R2-S2, 22.4R3, 23.2R1, and all subsequent releases.
Is CVE-2024-21606 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21606 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-2024-21606?
CVE-2024-21606 affects Juniper Networks Junos OS.
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