Cyber Resilience

CVE-2024-39529

Juniper Junos ≤ 21.4

Published
11 July 2024
Modified
21 November 2024
Patch / 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 0.0048 39th percentile
Risk Priority 45 floored blend · peak EPSS

Summary

CVE-2024-39529 is a high-severity Use of Externally-Controlled Format String (CWE-134) vulnerability in Juniper Junos. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 39th 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 SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

A Use of Externally-Controlled Format String vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). If DNS Domain Generation Algorithm (DGA) detection or tunnel…

more

detection, and DNS-filtering traceoptions are configured, and specific valid transit DNS traffic is received this causes a PFE crash and restart, leading to a Denial of Service. This issue affects Junos OS: * All versions before 21.4R3-S6, * 22.2 versions before 22.2R3-S3, * 22.3 versions before 22.3R3-S3, * 22.4 versions before 22.4R3, * 23.2 versions before 23.2R2.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
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.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-21606Same product: Juniper Junos
CVE-2023-22411Same product: Juniper Junos
CVE-2023-36838Same product: Juniper Junos
CVE-2023-36831Same product: Juniper Junos
CVE-2023-36845Same product: Juniper Junos
CVE-2023-22416Same product: Juniper Junos
CVE-2023-22394Same product: Juniper Junos
CVE-2023-36846Same product: Juniper Junos
CVE-2024-30391Same product: Juniper Junos
CVE-2023-22409Same product: Juniper Junos

Affected Assets

juniper
junos
21.4, 22.2, 22.3, 22.4, 23.2 · ≤ 21.4

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and static analysis can discover format-string vulnerabilities before deployment.

Input validation can reject or sanitize externally supplied format strings before they reach formatting functions.

Secure development standards and tools can mandate use of static format strings or safe formatting APIs.

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 prevent external format strings via code review, static analysis, and safe APIs.

ID.RA-01 partial match
prevents

Vulnerability identification can discover existing format-string flaws but does not prevent their introduction.

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.

finds

Security testing in development can detect format-string vulnerabilities before release.

prevents

Secure SDLC mandates input validation and safe API usage that can prevent externally-controlled format strings.

prevents

Application security requirements can specify safe formatting functions and ban uncontrolled format strings.

prevents

Secure architecture principles discourage dangerous string-handling patterns that lead to format-string issues.

prevents

Secure coding standards directly forbid the use of untrusted format strings and prescribe safe alternatives.

References