CVE-2024-39540

Junos OS: SRX Series, and MX Series with SPC3: Specific valid TCP traffic can cause a pfe crash

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS on SRX Series, and MX Series with SPC3 allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). When an affected device receives specific valid TCP traffic, the pfe crashes and restarts leading to a momentary but complete service outage. This issue affects Junos OS: 21.2 releases from 21.2R3-S5 before 21.2R3-S6. This issue does not affect earlier or later releases.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 21.2R3-S6.

Workaround:

  • There are no known workarounds for this issue.

Category

8.7
CVSS
Severity: High
CVSS 4.0 •
CVSS 3.1 •
EPSS 0.28%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA83000 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2024-39540?
CVE-2024-39540 has been scored as a high severity vulnerability.
How to fix CVE-2024-39540?
To fix CVE-2024-39540: The following software releases have been updated to resolve this specific issue: 21.2R3-S6.
Is CVE-2024-39540 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-39540 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-2024-39540?
CVE-2024-39540 affects Juniper Networks Junos OS.
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