CVE-2026-57022: CWE-754 Improper Check for Unusual or Exceptional Conditions in Juniper Networks Junos OS
CVE-2026-57022 is a medium severity vulnerability in Juniper Networks Junos OS affecting MX Series with SPC3, SRX5k Series with SPC3, SRX1600, SRX2300, SRX4000, and vSRX Series. It involves an improper check for unusual or exceptional conditions in the Packet Forwarding Engine (PFE), which can be triggered by an unauthenticated network attacker. When the affected device initiates a TCP connection to a malicious system that sends a specific packet, the PFE crashes and restarts, causing a temporary denial of service affecting all services until recovery. This issue can occur in scenarios including ALG, SSL proxy, UTM, RTLOG, AppQoE probing, AAMW, ICAP, and URL filtering. The vulnerability affects all versions before 23.2R2-S4, 23.4 versions before 23.4R2-S5, and 24.2 versions before 24.2R2.
AI Analysis
Technical Summary
An improper check for unusual or exceptional conditions vulnerability (CWE-754) exists in the Packet Forwarding Engine of Juniper Networks Junos OS on MX with SPC3 and SRX Series devices. An unauthenticated network-based attacker can cause a denial of service by triggering a PFE crash and restart through a crafted TCP response packet when the device initiates a connection to the attacker-controlled system. This affects multiple service scenarios such as ALG, SSL proxy, UTM, and others. The vulnerability impacts Junos OS versions prior to 23.2R2-S4, 23.4 versions prior to 23.4R2-S5, and 24.2 versions prior to 24.2R2 on specified hardware platforms.
Potential Impact
Successful exploitation results in a denial-of-service condition due to a crash and restart of the Packet Forwarding Engine, temporarily disrupting all services on the affected device until automatic recovery completes. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is stated in the available data. Users should monitor Juniper Networks advisories for updates and apply patches once available.
CVE-2026-57022: CWE-754 Improper Check for Unusual or Exceptional Conditions in Juniper Networks Junos OS
Description
CVE-2026-57022 is a medium severity vulnerability in Juniper Networks Junos OS affecting MX Series with SPC3, SRX5k Series with SPC3, SRX1600, SRX2300, SRX4000, and vSRX Series. It involves an improper check for unusual or exceptional conditions in the Packet Forwarding Engine (PFE), which can be triggered by an unauthenticated network attacker. When the affected device initiates a TCP connection to a malicious system that sends a specific packet, the PFE crashes and restarts, causing a temporary denial of service affecting all services until recovery. This issue can occur in scenarios including ALG, SSL proxy, UTM, RTLOG, AppQoE probing, AAMW, ICAP, and URL filtering. The vulnerability affects all versions before 23.2R2-S4, 23.4 versions before 23.4R2-S5, and 24.2 versions before 24.2R2.
CVSS v3.1
Score 5.9medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An improper check for unusual or exceptional conditions vulnerability (CWE-754) exists in the Packet Forwarding Engine of Juniper Networks Junos OS on MX with SPC3 and SRX Series devices. An unauthenticated network-based attacker can cause a denial of service by triggering a PFE crash and restart through a crafted TCP response packet when the device initiates a connection to the attacker-controlled system. This affects multiple service scenarios such as ALG, SSL proxy, UTM, and others. The vulnerability impacts Junos OS versions prior to 23.2R2-S4, 23.4 versions prior to 23.4R2-S5, and 24.2 versions prior to 24.2R2 on specified hardware platforms.
Potential Impact
Successful exploitation results in a denial-of-service condition due to a crash and restart of the Packet Forwarding Engine, temporarily disrupting all services on the affected device until automatic recovery completes. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is stated in the available data. Users should monitor Juniper Networks advisories for updates and apply patches once available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- juniper
- Date Reserved
- 2026-06-23T16:27:00.248Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a50171668715ace431ea1f3
Added to database: 07/09/2026, 21:48:06 UTC
Last enriched: 07/09/2026, 22:04:25 UTC
Last updated: 07/09/2026, 23:59:05 UTC
Views: 4
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