CVE-2024-39536

Junos OS and Junos OS Evolved: Flaps of BFD sessions with authentication cause a ppmd memory leak

Description

A Missing Release of Memory after Effective Lifetime vulnerability in the Periodic Packet Management Daemon (ppmd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause a Denial-of-Service (DoS). When a BFD session configured with authentication flaps, ppmd memory can leak. Whether the leak happens depends on a race condition which is outside the attackers control. This issue only affects BFD operating in distributed aka delegated (which is the default behavior) or inline mode. Whether the leak occurs can be monitored with the following CLI command: > show ppm request-queue FPC     Pending-request fpc0                   2 request-total-pending: 2 where a continuously increasing number of pending requests is indicative of the leak.  This issue affects: Junos OS: * All versions before 21.2R3-S8, * 21.4 versions before 21.4R3-S7, * 22.1 versions before 22.1R3-S4, * 22.2 versions before 22.2R3-S4, * 22.3 versions before 22.3R3, * 22.4 versions before 22.4R2-S2, 22.4R3. Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * 21.4-EVO versions before 21.4R3-S7-EVO, * 22.2-EVO versions before 22.2R3-S4-EVO, * 22.3-EVO versions before 22.3R3-EVO, * 22.4-EVO versions before 22.4R3-EVO.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 21.2R3-S8, 21.4R3-S7, 22.1R3-S4, 22.2R3-S4, 22.3R3, 22.4R2-S2, 22.4R3, 23.2R1, and all subsequent releases; Junos OS Evolved: 21.2R3-S8-EVO, 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-EVO, 22.4R3-EVO, 23.2R1-EVO, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

6.0
CVSS
Severity: Medium
CVSS 4.0 •
CVSS 3.1 •
EPSS 0.05%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2024-39536?
CVE-2024-39536 has been scored as a medium severity vulnerability.
How to fix CVE-2024-39536?
To fix CVE-2024-39536: The following software releases have been updated to resolve this specific issue: Junos OS: 21.2R3-S8, 21.4R3-S7, 22.1R3-S4, 22.2R3-S4, 22.3R3, 22.4R2-S2, 22.4R3, 23.2R1, and all subsequent releases; Junos OS Evolved: 21.2R3-S8-EVO, 21.4R3-S7-EVO, 22.2R3-S4-EVO, 22.3R3-EVO, 22.4R3-EVO, 23.2R1-EVO, and all subsequent releases.
Is CVE-2024-39536 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-39536 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-2024-39536?
CVE-2024-39536 affects Juniper Networks Junos OS, Juniper Networks Junos OS Evolved.
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