CVE-2026-57022
published 2026-07-09CVE-2026-57022: An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX with SPC3 and…
PriorityP336medium5.9CVSS 3.1
AVNACHPRNUINSUCNINAH
EPSS
0.40%
32.8th percentile
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX with SPC3 and SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
When an affected device initiates a TCP connection to an attacker-controlled system that responds with a specific packet, this causes a PFE crash and restart, which affects all services until the system has automatically recovered.
This issue can happen among others in the following scenarios: ALG, SSL proxy, UTM, RTLOG, AppQoE probing, AAMW, ICAP, URL filtering.
This issue affects Junos OS on MX Series with SPC3, SRX5k Series with SPC3, SRX1600 Series, SRX2300 Series, SRX4000 Series, and vSRX Series:
* all versions before 23.2R2-S4,
* 23.4 versions before 23.4R2-S5,
* 24.2 versions before 24.2R2.
Affected
25 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| juniper | junos | < 23.2 | 23.2 |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper_networks | junos_os | < 23.2R2-S4 | 23.2R2-S4 |
| juniper_networks | junos_os | >= 23.4 < 23.4R2-S5 | 23.4R2-S5 |
| juniper_networks | junos_os | >= 24.2 < 24.2R2 | 24.2R2 |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.2HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:A/V:X/RE:M/U:X
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VulDB
Juniper Junos OS up to 23.2R2-S3/23.4R2-S4/24.2R1 Packet Forwarding Engine denial of service
vuldb·2026-07-10·CVSS 5.9
CVE-2026-57022 [MEDIUM] Juniper Junos OS up to 23.2R2-S3/23.4R2-S4/24.2R1 Packet Forwarding Engine denial of service
A vulnerability was found in Juniper Junos OS up to 23.2R2-S3/23.4R2-S4/24.2R1. It has been classified as critical. Affected by this vulnerability is an unknown functionality of the component Packet Forwarding Engine. The manipulation leads to denial of service.
This vulnerability is listed as CVE-2026-57022. The attack may be initiated remotely. There is no available exploit.
GHSA
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX with SPC3 and SRX Series allows an unauthenticated, netwo
ghsa_unreviewed·2026-07-10
CVE-2026-57022 [HIGH] CWE-754 An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX with SPC3 and SRX Series allows an unauthenticated, netwo
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX with SPC3 and SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
When an affected device initiates a TCP connection to an attacker-controlled system that responds with a specific packet, this causes a PFE crash and restart, which affects all services until the system has automatically recovered.
This issue can happen among others in the following scenarios: ALG, SSL proxy, UTM, RTLOG, AppQoE probing, AAMW, ICAP, URL filtering.
This issue affects Junos OS on MX Series with SPC3, SRX5k Series with SPC3, SRX1600 Series, SRX2300 Series, SRX4000 Series, and vSRX Series:
* all versions before 23.2R2-S4,
* 2
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-09
Published