CVE-2024-39535: acx7020 — Fix

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved on ACX 7000 Series allows an unauthenticated, adjacent attacker to cause a Denial-of-Service (DoS). When a device has a Layer 3 or an IRB interface configured in a VPLS instance and specific traffic is received, the evo-pfemand processes crashes which causes a service outage for the respective FPC until the system is recovered manually. This issue only affects Junos OS Evolved 22.4R2-S1 and 22.4R2-S2 releases and is fixed in 22.4R3. No other releases are affected.

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CVSS v3.1 Score

6.5

MEDIUM

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

Weakness Type (CWE)

CWE-754 CWE-754

Affected Products

Vendor	Product	Versions
juniper	junos_os_evolved	All
juniper	junos_os_evolved	All
juniper	acx7020	All
juniper	acx7024	All
juniper	acx7024x	All
juniper	acx7100	All
juniper	acx7300	All
juniper	acx7509	All

References

Advisories & Patches

https://supportportal.juniper.net/JSA82995 https://supportportal.juniper.net/JSA82995

Frequently Asked Questions

What is CVE-2024-39535? +

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved on ACX 7000 Series allows an unauthenticated, adjacent attacker to cause a Denial-of-Service (DoS). When a device has a Layer 3 or an IRB interface configured in a VPLS instance and specific traffic is received, the evo-pfemand processes crashes which causes a service outage for the respective FPC until the system is recovered manually. This issue only affects Junos OS Evolved 22.4R2-S1 and 22.4R2-S2 releases and is fixed in 22.4R3. No other releases are affected. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2024-39535? +

CVE-2024-39535 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-39535? +

CVE-2024-39535 affects products from juniper, specifically: acx7020, acx7024, acx7024x, acx7100, acx7300, acx7509, junos_os_evolved. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-39535? +

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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