CVE-2024-21601

CVE-2024-21601 is a medium-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-362.

Key facts

Description

A Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in the Flow-processing Daemon (flowd) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos). On SRX Series devices when two different threads try to simultaneously process a queue which is used for TCP events flowd will crash. One of these threads can not be triggered externally, so the exploitation of this race condition is outside the attackers direct control. Continued exploitation of this issue will lead to a sustained DoS. This issue affects Juniper Networks Junos OS: * 21.2 versions earlier than 21.2R3-S5; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S4; * 22.1 versions earlier than 22.1R3-S3; * 22.2 versions earlier than 22.2R3-S1; * 22.3 versions earlier than 22.3R2-S2, 22.3R3; * 22.4 versions earlier than 22.4R2-S1, 22.4R3. This issue does not affect Juniper Networks Junos OS versions earlier than 21.2R1.

Frequently asked questions

What is CVE-2024-21601?
A Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in the Flow-processing Daemon (flowd) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos). On SRX Series devices when two different threads try to simultaneously process a queue which is used for TCP events flowd will crash. One of these threads can not be triggered externally, so the exploitation of this race condition is outside the attackers direct control. Continued exploitation of this issue will lead to a sustained DoS. This issue affects Juniper Networks Junos OS: * 21.2 versions earlier than 21.2R3-S5; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S4; * 22.1 versions earlier than 22.1R3-S3; * 22.2 versions earlier than 22.2R3-S1; * 22.3 versions earlier than 22.3R2-S2, 22.3R3; * 22.4 versions earlier than 22.4R2-S1, 22.4R3. This issue does not affect Juniper Networks Junos OS versions earlier than 21.2R1.
How severe is CVE-2024-21601?
CVE-2024-21601 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-21601 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-21601?
CVE-2024-21601 primarily affects Juniper Junos. In total, 64 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-21601?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-21601 have an EU (EUVD) identifier?
Yes. CVE-2024-21601 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-19249.
When was CVE-2024-21601 published?
CVE-2024-21601 was published on 2024-01-12 and last updated on 2026-06-17.

References

Affected products (64)

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