CVE-2024-39542: junos — Fix

Description

An Improper Validation of Syntactic Correctness of Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series with MPC10/11 or LC9600, MX304, and Junos OS Evolved on ACX Series and PTX Series allows an unauthenticated, network based attacker to cause a Denial-of-Service (DoS). This issue can occur in two scenarios: 1. If a device, which is configured with SFLOW and ECMP, receives specific valid transit traffic, which is subject to sampling, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. (This scenario is only applicable to PTX but not to ACX or MX.) 2. If a device receives a malformed CFM packet on an interface configured with CFM, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. Please note that the CVSS score is for the formally more severe issue 1. The CVSS score for scenario 2. is: 6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) This issue affects Junos OS: * All versions before 21.2R3-S4, * 21.4 versions before 21.4R2, * 22.2 versions before 22.2R3-S2; Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * 21.4 versions before 21.4R2-EVO.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-1286 CWE-1286

Affected Products

Vendor	Product	Versions
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All

References

Advisories & Patches

https://supportportal.juniper.net/JSA83002 https://supportportal.juniper.net/JSA83002

Frequently Asked Questions

What is CVE-2024-39542? +

An Improper Validation of Syntactic Correctness of Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series with MPC10/11 or LC9600, MX304, and Junos OS Evolved on ACX Series and PTX Series allows an unauthenticated, network based attacker to cause a Denial-of-Service (DoS). This issue can occur in two scenarios: 1. If a device, which is configured with SFLOW and ECMP, receives specific valid transit traffic, which is subject to sampling, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. (This scenario is only applicable to PTX but not to ACX or MX.) 2. If a device receives a malformed CFM packet on an interface configured with CFM, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. Please note that the CVSS score is for the formally more severe issue 1. The CVSS score for scenario 2. is: 6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) This issue affects Junos OS: * All versions before 21.2R3-S4, * 21.4 versions before 21.4R2, * 22.2 versions before 22.2R3-S2; Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * 21.4 versions before 21.4R2-EVO. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-39542? +

CVE-2024-39542 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-39542? +

CVE-2024-39542 affects products from juniper, specifically: junos, junos_os_evolved. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-39542? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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