Junos OS Evolved: ACX 7000 Series: When specific traffic is received in a VPLS scenario evo-pfemand crashes
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Juniper | Junos OS Evolved | 22.4R2-S1-EVO to before 22.4R3-EVO | 22.4R3-EVO | Patch available | CNA |
- Junos OS Evolved VendorJuniper Affected 22.4R2-S1-EVO to before 22.4R3-EVO Fixed in 22.4R3-EVO Patch available CNA
CPE configurations NVD · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:juniper:junos_os_evolved:22.4:r2-s1:*:*:*:*:*:* | 22.4 r2-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos_os_evolved:22.4:r2-s2:*:*:*:*:*:* | 22.4 r2-s2 | Vulnerable | Juniper |
| cpe:2.3:h:juniper:acx7020:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Juniper |
| cpe:2.3:h:juniper:acx7024:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Juniper |
| cpe:2.3:h:juniper:acx7024x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Juniper |
| cpe:2.3:h:juniper:acx7100:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Juniper |
| cpe:2.3:h:juniper:acx7300:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Juniper |
| cpe:2.3:h:juniper:acx7509:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Juniper |
- cpe:2.3:o:juniper:junos_os_evolved:22.4:r2-s1:*:*:*:*:*:* Versions 22.4 r2-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos_os_evolved:22.4:r2-s2:*:*:*:*:*:* Versions 22.4 r2-s2 Vulnerable ·Juniper
- cpe:2.3:h:juniper:acx7020:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
- cpe:2.3:h:juniper:acx7024:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
- cpe:2.3:h:juniper:acx7024x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
- cpe:2.3:h:juniper:acx7100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
- cpe:2.3:h:juniper:acx7300:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
- cpe:2.3:h:juniper:acx7509:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
Remediation
- Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 22.4R3-EVO
Timeline
- 2026-10-02 Threatist record created from CVE-2024-39535
- 2026-10-03 Alias added: GHSA-j93h-6wmf-9mh5
References
More Juniper Junos Os Evolved vulnerabilities
- TI-2026-17602 Junos OS Evolved: PTX Series: A vulnerability allows a unauthenticated, network-based attacker to execute code as root CVSS 4.0CRITICAL 9.3
- TI-2026-17601 Junos OS and Junos OS Evolved: Configuration of a specific SSH option results in mgd crash CVSS 4.0MEDIUM 6.7
- TI-2023-04136 Improper input validation in Juniper Junos OS CVSS 3.1HIGH 7.5
- TI-2026-74215 Stack-based buffer overflow in Junos OS rpd triggered by BGP peers CVSS 4.0CRITICAL 9.3
- TI-2026-74211 Authentication bypass in Juniper J-Web allows pre-auth CGI execution CVSS 4.0CRITICAL 9.3
- TI-2021-00146 Junos OS and Junos OS Evolved: Upon receipt of a specific BGP FlowSpec message network traffic may be disrupted. CVSS 3.1CRITICAL 10.0
Sources
- CVE-2024-39535 · CVE Program
- CVE-2024-39535 · NVD
- FIRST EPSS
- GHSA-j93h-6wmf-9mh5 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences