Cyber Resilience

CVE-2024-39531

Juniper Junos Os Evolved ≤ 21.4

Published
11 July 2024
Modified
22 January 2026
Patch / advisory
View advisory
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/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:X/V:X/RE:X/U:X
EPSS Score 0.0044 36th percentile
Risk Priority 45 floored blend · peak EPSS

Summary

CVE-2024-39531 is a high-severity Improper Handling of Values (CWE-229) vulnerability in Juniper Junos Os Evolved. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 36th 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 SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

An Improper Handling of Values vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved on ACX 7000 Series allows a network-based, unauthenticated attacker to cause a Denial-of-Service (DoS). If a value is configured for DDoS bandwidth…

more

or burst parameters for any protocol in a queue, all protocols which share the same queue will have their bandwidth or burst value changed to the new value. If, for example, OSPF was configured with a certain bandwidth value, ISIS would also be limited to this value. So inadvertently either the control plane is open for a high level of specific traffic which was supposed to be limited to a lower value, or the limit for a certain protocol is so low that chances to succeed with a volumetric DoS attack are significantly increased. This issue affects Junos OS Evolved on ACX 7000 Series: * All versions before 21.4R3-S7-EVO, * 22.1 versions before 22.1R3-S6-EVO, * 22.2 versions before 22.2R3-S3-EVO, * 22.3 versions before 22.3R3-S3-EVO, * 22.4 versions before 22.4R3-S2-EVO, * 23.2 versions before 23.2R2-EVO, * 23.4 versions before 23.4R1-S1-EVO, 23.4R2-EVO.

CWE(s)
CWE-229

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
T1687 Exploitation for Defense Impairment Defense Impairment
Adversaries may exploit vulnerabilities in security software, infrastructure, or defensive components to degrade, disable, or otherwise continue to impair their ability to prevent, detect, or respond to malicious activity.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-39538Same product: Juniper Acx7020
CVE-2024-39537Same product: Juniper Acx7020
CVE-2024-47490Same product: Juniper Acx7020
CVE-2024-39535Same product: Juniper Acx7020
CVE-2024-47489Same product: Juniper Acx7020
CVE-2024-30406Same product: Juniper Acx7020
CVE-2023-22402Same product: Juniper Junos Os Evolved
CVE-2026-21911Same product: Juniper Junos Os Evolved
CVE-2023-22398Same product: Juniper Junos Os Evolved
CVE-2023-44177Same product: Juniper Junos Os Evolved

Affected Assets

juniper
junos os evolved
21.4, 22.1, 22.2, 22.3, 22.4 · ≤ 21.4

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SI-10 Information Input Validation good match

Input validation directly enforces correct handling of parameter counts and defined values before processing occurs.

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 SDLC practices directly require proper input validation and parameter handling to prevent this weakness.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect missing-value flaws but does not itself implement the handling logic.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle includes input validation and parameter handling requirements that reduce missing-value errors.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for validation of all input parameters and fields.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles encourage robust input handling but do not directly specify value-count checks.

A.8.28 Secure coding partial match
prevents

Secure coding standards mandate proper handling of missing or undefined parameters, directly addressing this weakness.

References