Cyber Resilience

CVE-2026-57022

Juniper Junos ≤ 23.2

Published
09 July 2026
Modified
14 July 2026
Patch / advisory
CVSS Score v4 8.2
Click a component to see what it means
Raw vectorCVSS: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
EPSS Score 0.0029 21th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-57022 is a high-severity Improper Check for Unusual or Exceptional Conditions (CWE-754) vulnerability in Juniper Junos. Its CVSS base score is 8.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Network Denial of Service (T1498); ranked at the 21th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-7 (Boundary Protection) and SI-2 (Flaw Remediation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

No EU or UK CSIRT advisories indexed for this CVE.

Vulnerability Data

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1498 Network Denial of Service Impact
Adversaries may perform Network Denial of Service (DoS) attacks to degrade or block the availability of targeted resources to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

The vulnerability allows an unauthenticated network attacker to trigger a PFE crash via a crafted TCP response, resulting in a DoS condition. This maps to T1498 (Network Denial of Service) for the network-based impact and T1499.004 (Application or System Exploitation) for causing a system crash through exploitation of a software flaw.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-33790Same product: Juniper Junos
CVE-2025-52981Same product: Juniper Junos
CVE-2024-39545Same product: Juniper Junos
CVE-2025-59958Same vendor: Juniper
CVE-2024-21586Same product: Juniper Junos
CVE-2023-44198Same product: Juniper Junos
CVE-2024-39540Same product: Juniper Junos
CVE-2026-57023Same product: Juniper Junos
CVE-2026-57026Same product: Juniper Junos
CVE-2025-60004Same product: Juniper Junos

Affected Assets

juniper
junos
23.2, 23.4, 24.2 · ≤ 23.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SC-7 Boundary Protection
  • SI-2 Flaw Remediation
Detect
Catch it (NIST detect / respond)
  • SI-4 System Monitoring
Harden
Shrink the surface (DISA STIG)
  • 7 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Boundary protection at network and application-layer gateways (ALG, SSL proxy, URL filtering, etc.) can block or sanitize the attacker-controlled TCP responses that trigger the PFE crash.

detect

Continuous system monitoring can detect anomalous TCP traffic patterns or PFE crash events indicative of this specific exception-handling flaw.

prevent

Timely application of vendor patches (to 23.2R2-S4, 23.4R2-S5, or 24.2R2) directly eliminates the improper exception check in the PFE.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure development practices directly require proper checks and handling for exceptional conditions throughout the SDLC.

DE.CM-09 partial match
prevents

Runtime monitoring of software and environments can detect adverse events triggered by unhandled exceptional conditions.

PR.PS-04 partial match
prevents

Generating logs of exceptions and errors enables detection of improper handling of unusual conditions.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development and acceptance verifies handling of error and exceptional conditions.

A.8.15 Logging partial match
detects

Logging can record unhandled exceptions but does not prevent the weakness itself.

detects

Monitoring may detect symptoms of unhandled conditions but does not eliminate the root weakness.

prevents

Secure development life cycle mandates exception handling and input validation that directly prevent missing checks for unusual conditions.

prevents

Application security requirements explicitly call for handling of exceptional conditions and error paths.

prevents

Secure system architecture and engineering principles require robust error and exception handling mechanisms.

Hardening callouts derived

Configuration rules from DISA STIG baselines that reduce the attack surface for weaknesses of the type cited by this CVE. Derived transitively via CVE→CWE→STIG over `controls_xwalks` (authoritative rows only).

Oracle Linux 8 (2 rules)
  • V-248573 The OL 8 file integrity tool must notify the system administrator (SA) when changes to the baseline configuration or anomalies in the operation of any security functions are discovered within an organizationally defined frequency. via CWE-754
  • V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. via CWE-754
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. via CWE-754

References