CVE-2024-21606

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

State: Published
Severity: 7.5 High
Published: Jan 12, 2024
Updated: Jun 17, 2025
Reserved: Dec 27, 2023

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.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	juniper

Weaknesses

CWE-415 Double Free

Affected Products

Product	Versions
Junos OSJuniper Networks	before 20.4R3-S8Affected 21.2 to before 21.2R3-S6Affected 21.3 to before 21.3R3-S5Affected 21.4 to before 21.4R3-S5Affected 22.1 to before 22.1R3-S3Affected 22.2 to before 22.2R3-S3Affected 22.3 to before 22.3R3-S1Affected 22.4 to before 22.4R2-S2, 22.4R3Affected

References

https://supportportal.juniper.net/JSA75747vendor-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:Htechnical-description

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